Video joiner / splitter recommendations

can anybody recommend a good video joiner / splitter. it needs to be able to join 2 files of the same size,codec,resolution etc without re encoding.

free is preferable but i dont mind paying if its good, the program needs to be able to use multicores and if possible Nvidia cuda or its ATI equivalent (i dont remember the name) and do its job without any loss of quality and still be reasonably fast. i was considering ultra video joiner or boilsoft video joiner, has anybody had any experience with these programs ?.

Gazzer

 

Free Video Dub - freeware
http://www.dvdvideosoft.com/products/dvd/free-video-dub.htm

VideoCharge Studio - shareware
http://www.videocharge.com/Products/vcs/doc/without_reencoding.php

Boilsoft Video Joiner/Splitter - shareware
http://www.boilsoft.com/avi-mpeg-rm-joiner.html