ya but any full resolution uncompressed vid will takes gigs of space
even if you go from source recorder to avi
but i do believe the source recorder can compress to mpeg4 or what ever codecs you have on your system.
also since the recorder renders 1 frames at a time you can max out the games settings even if your computer cant handle it and still get a perfect fps in the vid it will just takes longer to render. (prolly dosnt matter now but it was what i did when source first came out and i had a shitty graphics card for vids.)