The trick with QTrapids is to save the .torrent file to the Micro SD card and get qtrapids to download the torrent files to the Micro SD card also.

As long as you don't use the internal memory, qtrapids works great (phone will be a little sluggish initially for first 5 mins then goes back to normal speed). I'm using KP50 overclocked to 900mhz and I usually get download speeds of around 250kbps.