I have one, given to me by my Mom (and she swore by them) but, as with so many of my kitchen things, the pressure cooker is packed right now. I've had some good results with it, though time does improve on things where pressure just cooks them fast. There are some things that you simply should not cook in pressure cookers. I think beans are one of those things, because they turn to mush and clog that "escape valve" as you call it, and can cause an explosion. Mom used to have one with a pressure guage, but I haven't seen any of those in years.

SRS