The STA is an extremely beautiful airplane, no question. When I was looking they were $100K or more. Parts, either airframe or engine were rare and expensive. The Menasco doesn't have the reliability of a Ranger, not by a long shot; pretty important in very old single engine aircraft.
The PT-22 is the dead sexiest of the three major WW2 basic trainers IMO. When I was looking they were ~$65k and the Kinner Master Rod was the weakest point of the aircraft. Master Rods were damn hard to find if you could find one at all. I think somebody eventually had a very small number made. Not sure of the status now. Rest of the parts are kinda tough too. The other thing I found off-putting for me was that at my height, half my face was above the rear windscreen in flight. This means bugs would smack you in your face and head at 90 mph. Very tight cockpit for a 6' 2" guy too.
The PT-19 is without doubt the easiest of the 3 trainers to fly, land in high crosswinds and also maintain. I bought mine for $30k with about 180 hours after complete strip down to frame and restore. Parts for engine and airframe are still relatively available compared to the Ryans. The cockpit is very roomy, even for big folks. The windscreen protects your face. The view, compared to Stearman is unbelievably better but then so is the view from a Ryan.
So, if I were a multi-millionaire, I'd have an STA. Probably wouldn't fly it much though. The -19? A blast to fly and a workhorse. I flew mine a bunch. Worst situation I was in was probably the day I got caught by surprise rain/thunderstorms the weather liar had not predicted. Even then the worry was the rain stripping the varnish off the Sensenich prop. It handled a MAJOR crosswind on a grass strip without a bit of trouble. I was glad I wasn't in a Stearman that day!