That said, I have
Presto 6 Quartwhich is only $50. It has a recessed locking mechanism, and it's shaped like their 'best value' pressure cooker that costs twice as much.
However, I've only really used it for stews so far, but for that it's been pretty awesome. I literally just made another stew for dinner tonight and the general recipe is pretty simple: brown meat, add liquid, cover and bring to pressure, cook for 8 minutes and then quickly release pressure by running the entire thing under cold tap water. Add potatoes/veggies and bring to pressure again, cook for 4 minutes, quickly release pressure again, and then serve.
I'm not huge on following recipes, but with a pressure cooker, you definitely need to, especially the first time to get the timing correct. Cook it for too long and your veggies turn to mush, too short and your meat is still tough. That said, though, there's still room for experimenting, like tonight I used half beer and half stock for the cooking liquid and it turned out great.
I'm living alone right now, and I think it's a good investment. It'll make enough for about 6 portions which works for me since I prefer to cook once and then eat leftovers for a few days.