You don't mention whether you own a DV camcorder. Many of them will do the conversion on the fly from S-video/RCA connections out of the VCR to the cam and firewire from cam to PC. D-8 cameras will read Hi8 tape and play it via firewire to the PC. I've done much of this with a Sony TRV 525 D-8. When it won't read out I send it to VHS and capture that. If you don't own or can't borrow a cam the Canopus product is a much cheaper solution over buying one.
David Hurdon