With those, you aren't going to pull out of the pedal by accident if they are set on the loosest tension. The screw is at the back of the pedal (there's a + and - sign and arrows). The cleat should be screwed on the shoe tightly! That could've been one reason you couldn't get out--you were twisting the cleat off the shoe instead of the cleat out of the pedal. IMO, I think that no matter how tight the tension is on those particular pedals, clipping out feels the same. What I cannot do when the tension is too tight is get clipped in! I can pretty much jump up and down on the thing and it won't engage.

If you still struggle with it after tightening down the cleats and loosening the pedal, there's always the "Keo Easy" pedals that have less tension.