misliz,
This Spring, I bought the new Shimano r600 spdl pedals and have had a HARD time clicking out of them, too. From reading your input, I think it's for the same reasons. Over the season, it's become a bit easier...but on my really long rides, I do notice that I get weaker in the clip - out. Hmmmm.
I bought these pedals with the thought that the wider platform would allow me to get more power to it in each stroke. My general impression while riding is that my foot does feel more secure or balanced, and I do have a sense that I'm getting more power to the pedal . Clicking out is the worst thing about them for me though. Very good info.