Wow, Never, you sure love that name.
If you come to Baltimore, my LFS has a bunch of Anableps. I'M NO EXPERT, but they look small enough to fit two into a 50 gal. But I wouldn't do more than 2. Of course, they overstock at the lfs, so they have like 10 in a 20 gal.
They seem to be very active fish also, and they stay at the surface. (from what I've seen)
If I had a big tank I would consisder it, but that's not going to happen for a year or 2. Trying to relocate back to Pittsburgh, which may take a few years. Don't want to start a huge tank until I settle down.