I don't think it is on the same level sonically as B-3X and Waterfall, but those don't have the part generation/ MIDI library(ies) of the EKX. The EKX also isn't as tweakable.
Simply put, the EKX isn't for B3 players, it is for people who can't play B3, but want organ in their music - it's not for "us," it is for "them".