I use this: http://www.bigasoft.com/wtv-converter.html to convert to XVID for a device that won't play MCE buddy mp4. It's $30 and has a GPU acceleration option. It doesn't remove commercials
and I haven't tried to remove commercials from the XVID files with either MCE Buddy or standalone Comskip.
A recorded ~6 GB .wtv file is converted to XVID in about 1 hr @ 1280x720 and normal quality conversion (Video Bitrate=10000).
Quite frankly, I don't notice any difference using the CUDA option over my previous onboard AMD video. However, I have never directly compared apples to apples. Sometimes I'm converting several files at once and sometimes just a single file and I don't know
how the bigasoft program works. That is, I don't know if it uses all cores on a single file conversion, or it always uses a single core/file no matter how many files are converting.
The machine I use is a triple core AMD Phenom II on a ECS Black mobo with 8 GB of RAM and a NVidia GT 630 card with 1 GB of GDDR5.