So, good question, the previous owner did install a vapor barrier covering the basement and crawlspace, so there is some other mitigation in place. The current unit came with the house - HOMELABS HME020031. It keeps humidity down fine, but the pump is broken, so I'd like to replace it with something that should last for a while and hopefully run a little lighter on electric cost.
It seems it has a rating of 1.9L/kwh, whereas the aprilaire is 2.3L/kwH, so I suppose about ~20% more efficient. My other thought was they seem to have a better warranty so if something fails then I don't need to replace the whole unit.