Additionally, about the worst possible hand for the villian to have here is Qs-Q-K-J, which gives the poster 25% equity. Against a range of very playable Q-Q hands, the poster is probably looking at 31-35% equity.

So, if Hero puts in 20BB into a 45BB pot, he is giving up roughly 4BB in the case where he is up against top set. So, it is a bit of a gamble, but not really anything to get all riled up about in the case of a check/call. He is also getting proper pot-odds on his call.

Note how much worse it is in the case of a bet/call. Hero still has the same equity, but instead he put in 60BB into a 125BB pot. Now, he is looking at an expected loss of 16BB.

Is a check/call the greatest play of all time in this case. Probably not! Is the worst play of all time. Probably not! Unless the Hero can narrow the Villian's hand range down to one or two very specific 4-card hands, then a check-call is somewhere between a very slighty +EV and very slightly -EV decision.