I bought my girlfriend one (or a PEN-EE.something at least), but she hasn't put a full roll through it yet, hehe. 72 shots out of a 36 exp roll! I played with it a bit though, one thing I did notice was that if you were too quick pushing the shutter down, it wouldn't have time to meter, and the aperture would be completely open when the shutter fired. Normally if the light is too light or dark for the camera to handle, the shutter release locks, and a red transparent flag comes up in the viewfinder, saving you from a bad shot, but not when you push it down real quick.
Another thing to note, at least for the camera I got, is that the metering only goes up to ISO 200.
The exposure counter does a weird spinning thing that counts down from where you set it instead of up and can be set to any number you wish even after the film is loaded... its rather odd.
Oh, and the back of the camera comes completely off, there's no hinge or anything, and I think it slides down, not straight out... It took me some time to figure it out, but the one I have is kinda old and probably stuck from not being used for a couple decades.
Hope you have fun if you get it!