Another vote of confidence here -- I have a P9 that has been flawless since day 1.
Whether or not it will feed reliably using the slide (as opposed to the slide release) seems to depend on the individual gun. Mine feeds fine using the slide.
I can recommend the Agrip adhesive grips -- they're great. Take your time putting it on. They add virtually no width to the gun and do not catch on your clothing.
In comparison with larger autos like the Glock 19, the recoil is a bit snappy and more difficult to control accurately, though it does seem manageable.