I am using this phone for past one month.(5800 xm). The best part of it is
-Very good looks...better than any other touch screen phones.
-easy to use compared to other touch phones
-value for money, it has gps , wifi, 3g and 8gb for just 20k
-amazing video playback more clarity than lcd display.. it is just amazing!
-very good external stereo......It is the best in any class.
The worst part is
-it is based on s60 5th edition(new) so many 3rd party application will not work.
-poor document viewer.. you have to buy adobe reader and cannot edit quick office.
-head phone sound is not adequate....some times its difficult to listen in loud surroundings.
-mobireader does not work.
-limited number of games...even to buy.
-camera is not up to the mark even-though it has dual flash, clarity is not good when compared to other 3.2 megapixel cameras.
Otherwise no technical problems. Considering all this put together I still recommend you to buy this phone for its looks, style, easy to use, amazing playback video.