It boils down to what is reasonable to expect from the Mystic guys. But I think one difficulty with picking koi out of a tub of 5 (not to mention 20) is that invariable, some of the koi will be at different angles, and some might have their bodies bent, and some might be covered by other koi, and some will appear bigger or stouter depending on angle. This makes picking that perfect one for some of us more difficult, particularly on a baby shiro utsuri where I think (?) we will be looking for any minor hints of pattern or motoguro to come or too much sumi or not enough sumi, etc. At least if they are somewhat in a typical glamor shot, the entire body and both fins can usually be seen. Regardless, it won't be easy to photograph and keep score, or to decide.

On the other hand, we can do what I think SuperKindai suggested, which is throw darts at the fish... err..
Koiczar, yeah, I understand. I don't know, would Omosako have some of the tosai sorted into grades (?). So it might be a matter of scooping the net into the vat with the proper grade, then giving them a once over to ensure nothing too poor (or too good) slipped by.
- Wayne, wants the tosai pictured that is at 1:00, second one to the left of the third largest one with the mouth open and the tail turning right.