I don't think there is any viable way YET to convert the mags to 3 plus. Even then - I have an old 20 rd Evo S1 that came with 20 rders that have the 3 plus cut, but they DON'T lock - figure that.
While the 3 plus is more "American" in its manual of arms, I like the paddle release. Also, they went from a HUGE weirdly angled grip to a much better angled but tiny grip. The one I just sent back to Cz as it has canted sights, it will not drop free with MP mags or ETS, so the easier mag button is pointless.