Personally, I've always thought of it as somewhat questionable. Especially given how they have permission from neither the company or the actual hacker/translation team...
I've actually seen that happen to Super Famicom fan translations of Clock Tower and Final Fantasy V. They're both auctioned at rather absurd prices online, though.
I think that serious collectors get more out of those, but what's wrong with owning the original Super Famicom cartridges? While the Japanese may turn many off, you'd be paying significantly less for a whole set than a Super Nintendo cartridge by itself.