Would echo these comments. Had this one about 2 years (original was replaced under warranty) and is in great shape, despite being in daily use. Although I was given an iPhone by my former employers ;-) , I prefer to use the Serene as my phone because a) I really only want to make calls with a phone and b) it's a little more interesting than the iPhone that everyone in the world now seems to have!
Actually, there is one irritation - I just said I only want to make calls, but given that it can do MMS and WAP, I sometimes like to give that a try - but (must have been since it was replaced 2 yrs ago LOL!) these functions no longer work. The settings are all present and (seemingly) correct but attempts to send a picture message just says 'not available' and if I open the WAP browser it locks the phone and I have to take the battery out before it will respond again... I have a SIM-only contract with T-Mobile in the UK and as I say I'm pretty sure both features worked initially.
No big deal, still loving Serene.
G.