It should be fine, but you'll lose the full HD resolution when you export the end result. Does it record to hard drive or tape? Unless you capture the raw vision straight to your computer's hard drive, and export a full HD movie, you'll end up with Standard Definition anyway. You'll also lose quality once you burn it to DVD, print to tape etc.
I'm not sure about 6.5 - are you capturing via firewaire or USB?
I work in TV and have access to plenty of editing goodies, so if you get stuck I can help you out. PM later in the week if you can't capture the footage and we'll devise a plan!