Pros: Packed w/ Smart Features, Expandable, Relatively good looking.
Cons: Buzzing noise generated in the base, poor outgoing audio.
As many has told, the major blow of this phone is the audio quality. After all, it is an important element. Though the incoming audio is clear, unwanted hissing noise can still be heard. Outgoing audio is below average. All of my friends share the same comment during my trial calls: My voice sounds synthetic or being in bad reception spots.
About the issue of short battery life, I do not think it can be standby for 80 hours as advertised but it is not that bad in my case either. I am not sure if the battery indicator gives me the false sense of security or the fact that I have put in two 1300 mAh NiMH AA cells. I recharge the handset every other day before I leave home. Talking about recharge the battery, I have found something rather annoying. There is a buzzing noise generated inside the base and easily audible when the handset is in the cradle during recharge.
Another potential problem I have heard from other users is interfering with 802.11b or 2.4GHz spectrum wireless computer devices. Microwave oven will also generate interference to this phone when heating your food. So do not place the base or use the handset near the Microwave oven. Even it will not be like constant static noise, thanks to the Digital Spread Spectrum technology, but you will rather get the annoying "pop-pop-pop" noise during calls.
Range is, however, acceptable in my case. Its footprint covers all the spots I stay in the most. The onboard answering machine works fine. The smart features packed electronic menu on the handset is the best thing you can find. Things like to turn on/off the answering machine from the handset, transfer the whole phone book to another handset (up to 4 handsets in total for 2415), intercom/conference call are among the goodies. The LCD display on the handset comes with backlit but it would be even better if the keypad lights up too.
This phone is something that I love and hate at the same time. Unless you are really into its relatively good look (Of course, B & O Beocom 6000 is the most handsome one), going to have multiple handsets in the house or you can get it at bargain price (like I did in demo sale), it is not worth to pay for the expensive price tag (Again, there is always something even more expensive like B & O).
UPDATED*** A fellow owner told me that the poor outgoing audio can be rectified by using a headset w/ boom microphone. Well, this way is not very convenient at home. But, it is acceptable to use with the belt clip.
So one of my friends (who has the sibling handset 242) go all the way to the root of the problem: He has replaced the microphone inside the handset! We are all amazed by his stunning act and the outgoing audio is IMMEDIATELY BETTER, MORE NATURAL than ever. But, DO NOT ATTEMPT to do it by yourself if you do not have the skills and access to the right tools for electronics. Open up the handset will not only void the warranty but will damage to the housing of the handset for sure!