I brought Sony Ericsson K550i around 5 months back and its a real cool mobile.
Best feature for why I had gone for this is, its from CYBERSHOT series. Basically Sony Ericsson is broadly working in two series i.e., Walkman & CYBERSHOT.
I had two mp3 players so, I desperately required a mobile in the middle range and with high resolution Camera. K550i is having photo fix, flash light, 2.25 xs zoom also auto focus, picture blogging by which you can send the photo instantly through online, video recording. This K550i with 2 MP cameras surely had done the purpose.
This is wonderful mobile because its web surfing experience due to 64MB phone memory and RAM is really fast. This mobile is coming under middle range and contain all features of a high priced mobile like blue tooth, speaker phone, blue tooth headset, expandable memory up to 2 GB, quad band which will make you go around almost every part of world with out service interruption, EDGE supported for high data rate browsing service. Also it is having a feature that you can directly via phone able the print the photos by printer. Along with Bluetooth, it also posses all these features i.e., infrared, synchronization with PC and USB detectable. It can be used as a modem to connect internet to your PC or laptop.
With all mind blowing features it is having media player, sound recorder and radio also.
Music quality over speaker phone is not that much good but over headphone it really sounds great. MMS is also supported and also you can send message with having sound clip attached in it.
With these entire interesting features some games are provided which are not too good but ok.
Now Talk time is up to 7 hours as claimed but I think around 4.5 hours it will easily work.
Value for money is kept intact in this mobile with such a huge interesting features I believe.
If planning to buy middle range mobile better go for this. Must be a nice option for u.