I have got a very performance tf card， I use atto to test it in my pc it can have a 16mb write and 20mb read result. When I use it to my droid , I use sdcard speed test app to test it , but the result disappointed me, it can only have a 6mb write and 7mb read performance. I guess it may be the rom cause the issue. So I changed my rom from Bugless 0.6.1 to CM6.1.2 ,and SS5.2,the result is stiil the same. Having realized the rom above is either 2.2 or 2.3, So I flashed to 2.1 at last， A miracle happened， It can have a 9mb write and 17mb read performance！！！ But I really do not go back to 2.1 version。 I really don't understand why cause this problem. Does droid 2.2 or higher firmware does'nt support high speed card, or probly has a limit to the card speed. Any one can help me solve the problem? My sincerely!