Based on what I'm seeing in the EE, determining gun values is getting tricky....especially if Marlin 795s/60's are suddenly worth some of these asking prices? lol
Since the OP didn't specify intended purpose, just "22 semi" then I wouldn't argue the 10/22 advice in this instance. I think the Marlin's I've had (3 x 795s) all shot better than the 10/22 I bought new, but they were light guns and didn't exude quality. They did behave as they should, and carried a lower price new-appropriately so.
As for what to go for, my own purchasing decisions support what I think-I got a Thompson T/CR22, a 10/22 clone made with improvements and in spite of the (green) stock that flexes a little, ergonomics are great and the gun can shoot. I've chilled-out on my opinion of Ruger 10/22s, but would still pick a T/CR22 over one today if I was getting a semi. I would still NOT pick a 64, but I have more experience handling/fixing them then I do shooting them.