The Plantronics 655 has a few great things going for it:* Sound quality* Style* Ease of use* Customer serviceI've been very impressed with the sound quality. My wife has one of the early ones from Treo and always tries to borrow mine instead. I've had an occasional problem if I'm in a very loud area but that's true even if I'm on my cell phone.The style is great - it's small and discrete. It stays in my ear very well, even without the loop. I also like that the case has a belt clip - I attach it to my phone's case and it goes well there.In terms of ease of use, the greatest thing is that I can leave it attached to my phone and answer calls by removing it from the case. While it is comfortable to leave in my ear, I would rather not do so and find it very easy to answer this way.I put customer service last but it's probably the most important. When I bought the 655, they shipped it with an attachment that goes on the bottom of the case. The USB cable plugged into the attachment. About six months after purchasing it, the attachment started to come apart. I called up Plantronics and was stunned that I was put on hold for exactly 0 seconds. After the guy answered the call, he processed my request very quickly and professionally and gave me the new kind of cable that goes directly into the case instead of the old attachment, which was more cumbersome. I didn't know that anyone offered that kind of customer service any more - and that's what will lead me to buy a Plantronics product the next time I'm in the market for one.