Yeah, it's not really worth much of anything other than as a proof-of-concept.
Only about 50% of the games will boot at all and only about 10-15% of them are playable all the way through without severe graphical glitches. It's not because there is some inherent problem running HuCards off a CD, but rather, memory addresses have to be adjusted throughout EVERY ROM for them to work from the CD. It's a lot of work, and whomever created the Super HuCard never finished converting the address calls. It could work 100%, but it doesn't in it's current state.
For me, it's mostly useful for playing the GunHed caravan mode which was omitted from the regular game cart. That is one of the few games that actually works 100%.