They are good fish, a little more shy than a clown but they only get to be 4-5" maybe just a touch longer. Much less mass vs a similar length clown.
(Lots of beady eyes under a log and then a massive mad half hour, I had mine in a 36" and gave them to my mate as I moved, I really couldn't keep them, he/she (they) had a 4ft x15" but double deep tank, the fish really came alive in that tank, maybe a 36" isn't quite enough, but that's my opinion based on my experience with the yo yo, they lived ok but they seemed happier with more space)
They are a great fish in a shoal, you'd be happy with 6-8 of those with no real need for an upgrade. Yes I'd say they are happier in a bigger tank but mine did ok for 3-6 years. Just with loads of clean water and some extra flow (basically one extra water change a week and an internal filter or power head along side your main filter)
They are more drab though being a sandy colour all over with brownish lines all over.
An even smaller good botiid is B.striata, more striking than the yo yo. Good snailer slightly more aggressive/territorial, Much smaller.
Seen, like, want, watched in captivity, but were in 40-48" tank.
They seemed to be enjoying themselves! But that's just loaches!
Slightly jealous D, I know you have some great fish in your tank!
I miss mine.