Pros: Smooth, quiet, computer makes workout interesting. Computer uses batteries or wall plug.
Cons: Heart rate monitor does not always seem accurate at the beginning of workout.
I tried out a Stamina EMR (Electro Magnetic Resistance) Series 55-1777 in a store, and really liked it. I read reviews (which I really appreciated) and looked around at many elliptical trainers, but could not find much information on the Stamina. I took a chance and purchased it ($499), and I am glad I did.
The specifics... This is a very smooth and quiet machine, and the computer reminds me of the ones in the gyms. It has a pulse monitor on a stationary handle bar, and programs to help monitor and control desired heart rate during the workout. There are also two moving handle bars for a cardiovascular workout.
* Computer. There are 16 programs, including 1 manual program (flat walking), 6 programs with hills, ramps, valleys, etc, 1 body fat program that helps find and program a personalized workout for burning fat, 4 heart rate control programs, and 4 user programmable programs. Depending on the program, you enter time, distance, age, gender, height, weight, and/or target heart rate. (The height and weight seem to be in metric, but I haven't played around much with that part yet.)
There are 10 different columns that blink to show progress. The column you are on blinks until the time is up, then the next column starts blinking. The automatic setting is 30 minutes (3 minutes per column), but can be set to less. When set to less, the time is divided out evenly in the 10 columns. (10 minutes makes 1 minute per column.) As I go, I can see my progress as the blinking column changes to the next column. I find this to be great motivation.
* Tension. There are 16 tension settings. The tension settings are pretty tight, so I don't think I will advance past the highest level, at least not for a very long time.
* Power. The computer uses either 4 C batteries, included, or an adapter that plugs in the wall, also included.
* Space. It is self-leveling and has rollers on the front that are supposed to make it easy to move. (It is pretty big, so I don't think I will try that any time soon!) The book says it recommends 7 ft of space during operation. I measured from the front bar at the bottom to the back bar and it is 50 inches. I measured across the handle bars (put on backwards - explained below) and it is about 28 inches.
Update: I moved it about 5 feet and it was much easier than I thought it would be. The machine did leave quite an indentation in the carpet after just a few months, so I am going to look into getting a mat to put under it.
My experience so far... Well, I am more out of shape than I realized. I can't say I have given it a very good workout, so I can't say anything about durability over time. I get on it a few times a day for as long as I can. I mostly use the flat program (simulating walking) on the lowest tension level, and I haven't gotten through 30 minutes yet. I have had it about a month now, and it is still as quiet and smooth as it was the first day.
Other machines I tried... I purchased a ProForm 675 from Sears on sale for $299. I brought it home and read the directions which said I needed 2 people to put it together. At that point, I started reading reviews and found several that talked about how hard it was to put together. There were some that even offered suggestions about how to add parts to it to keep it from being so noisy. I took it back and decided to spend a little more to get better quality. (Sears was great about taking it back and even got it out of the car for me.) I started to buy the next ProForm model ($399), but they were out. I decided to look around some more.
I tried a Tunturi C3 ($799), which I loved, at another store right before finding the Stamina. While the Stamina was not quite as smooth as the Tunturi C3, it was definitely smooth and had a lot more features for about half the price (counting warranty, pickup/delivery, etc).
When trying out machines, I put the tension control at different levels. I found that the mid-high levels were comfortable and wondered how soon I would advance past the highest level. I like the Stamina because there are more tension levels and because I am comfortable at the lowest level.
Putting it together... Probably not hard for most people, but took me about an hour and a half. The main part was already put together, and I only had to put on the handle bars, attach the foot part, and attach the computer. The instruction book was somewhat confusing, but seemed to be written in "regular" English (not "foreign" English).
If you are putting one of these together and don't know one screw size or bolt from another (like me), you can benefit from knowing the part that took me about an hour: There is a diagram at the front of the book that shows what different screws look like. This diagram does not necessarily show what screws are included; it only helps to identify the screws that are included. The parts list is in the back of the book. The parts lists shows ALL of the parts, including the ones already put together. I was getting very frustrated until I finally found a way to figure out which screw was which. I went through the directions and as I got to a part number, I wrote the part number on a small piece of paper, identified which part it was, then put all of the ones that looked like it together with the piece of paper. I did this until I identified all of the washers, screws, etc. (The screws for the computer were screwed into the back of the computer, so don't spend any time looking for them as I did.) After that, I had it put together in about a half hour.
I had read that it is best to stand up straight during the workout, and I thought I might be leaning too far forward. So, I switched the left and right handle bars. It was very easy to do because of the design of the machine. It seems to be working fine, but I can easily change them back anytime I want.
Warranty... I purchased the extended warranty as so many reviews recommended for elliptical machines that cost under $2000. The warranty was around $30 for 5 years of in-home service at Play It Again Sports, where I purchased my machine (new).