Pros: works well and as designed
Cons: no real thermostat and no timer
Need and purpose
We live in the Northeast and have central heating in our house. Last winter, in our old house, the heating failed twice (the second failure apparently caused by an installation error in fixing the first failure). We were lucky enough to get it repaired on the same day in each case, but it was a close call and we might well have ended up one or two nights without heat. I actually went to the local Home Depot trying to buy a space heater while the heat was out, but it was March and they had sold their complete inventory. Target had, too, and was offering air conditioners instead!
So this winter I decided to plan ahead and buy space heaters in the fall. After reading up a bit on the merits of different styles, I decided to go for an oil-filled radiator-style model. Sears advertised a sale on this model (for $39.99 instead of the regular $49.99), so I decided to buy four of them to have enough to heat all bedrooms in case of a failure of the central heating system. I also figured that a space heater would be cheaper if just one room (i.e. the living room) had to be heated during large parts of the day.
This heater only has a simple thermostat with six numbered settings (1-6) plus a low anti-freeze setting. Obviously, those settings will roughly correspond to temperatures (or rather temperature ranges), but you can only find out by trial and error. A thermostat that allows the setting of target temperatures in degrees Fahrenheit would be much nicer. More expensive models from Delonghi (and other manufacturers) have those. Those other models also often have timers which allow some programming of the heater to go on and off at specified times. All those are useful features which this basic model is lacking. However, I think that for our purposes, which are mainly to provide supplemental and backup heat, the simple model is sufficient. If you are planning to use the Delonghi heater as your primary heat source, you might want to get a more sophisticated model with a real thermostat and a timer - they may cost you $20-30 more, although you can probably also find models that cost more than $100.
The heater is advertised as "safe to touch". That is true, but it still gets quite hot and moving it with bare hands while on isn't so easy, especially not on a carpet where the wheels don't roll very well. I am not sure how safe it would be to have the heater on overnight in the room of a small child, say a 2-year-old. There would probably be enough time for the child to realize it touched something hot and to withdraw without getting burned, but I probably wouldn't want to conduct this experiment. And certainly not if there is any chance of a child falling against the heater and not being able to get away from it - that could be quite dangerous.
Definitely in need of improvement is the manual that comes with the heater. It is written in rather bad English and contains odd advice like (quoted from memory) "don't use an extension cord, but an extension cord may be used" or "place the heater under a window, or anywhere else in the room" or "don't place the heater under a power outlet" (huh?).
The heater requires no real maintenance - and, in case you were wondering, no oil ever comes out of the heater (unless you manage to break it...) or ever has to be refilled.
The three settings, "low", "medium" and "high", are not all that useful. Particularly odd is that the "low" setting is 700 W and the "medium" 800 W. The "high" setting is simply the combination of the two, i.e. 1500 W. Unless you really just need a little bit of extra heat, you will probably want to go for the "high" setting.
Worth realizing is that the heater will cost you about 15 cents per hour on "high" at an electricity rate of 10 c/kWh. That may not sound like a lot, but if you have it on the whole day, it adds up to $3.60 per day or $108/month.
Also worth noting is that in most American homes you will only be able to run one heater on the same circuit at the same time. While one heater per average-sized room is usually enough, if you have two rooms on the same circuit, you can only heat one of those rooms (and we were surprised to find that our house has three rooms on the same circuit, one of which is on a different floor from the others!).
So how well does the heater actually work?
It takes a few minutes to get hot, which is unavoidable for this kind of heater. If you want instant heat, you have to get a fan heater that instantly produces hot air and blows it at you. I found fan heaters to be not very effective at warming up a whole room, especially not at the 1500 W level at which almost all of them operate in America (in Europe heaters and all other electrical devices can run at up to 3000 W since voltage is twice as high there - that makes quite a difference for heaters!).
Once it's hot, it radiates heat which can be felt up to a few feet away from the heater. Not very far, though, and if you really want to warm up yourself, you probably want to get as close as possible to the heater as you can.
It takes a while for the heat to spread and to warm up a room. The room does not get uniformly warm, and it definitely depends on where the heater is placed. The somewhat cryptic advice from the manual to put it near a window is probably a good idea.
I think this model works as designed and does what it's supposed to do, but don't expect any miracles from it. In warm climates this kind of heater may be sufficient on its own to get through the occasional cold night, in colder climates this heater will only work as a supplement to an existing heating system - to help heating rooms where the central heating doesn't produce enough heat or where it doesn't get to, such as an attic or a basement - or to provide some warmth in individual rooms on days where it doesn't seem quite cold enough yet to switch on the central heating system.
To comparison shop for an oil-filled radiator-style heater seems a rather hopeless undertaking. There are so many different models around (even from Delonghi alone!) that no two stores seem to sell exactly the same model. This particular model is only sold by Sears, it appears. I guess this is an interesting way of ensuring that their "low-price guarantee", which of course only applies to the exact same model, is completely worthless, as those kinds of guarantees usually are.
Delonghi claims that their heater is better than comparable heaters in certain ways, but presumably the competitors make similar claims. One of the claims is that it uses less energy than comparable models, which I found a rather bogus claim, since all heaters I have seen advertised use 1500 W and much more than that is practically impossible with 110 V (some hair dryers seem to be pushing the envelope at 1875 W). I saw a very similar heater by a different manufacturer at a Home Depot soon after I bought this one at Sears, and it was $5 cheaper. Whether it would have been just as good, but possibly even better I will probably never know.
The best time to buy a heater is probably in the fall, when the selection is greatest, or whenever stores to decide to dispose of their remaining inventory before stocking up on air conditioners and lawn mowers (that might be pretty soon). But once you have missed that window of opportunity, you may be out of luck, especially if you need a heater right away. You can probably order them online at any time, but shipping costs might make that option rather expensive (these heaters are pretty heavy, although not too heavy to lift them by an average person).