I have a cxp APE and have run it for a couple of years now with no issues, can be a little picky on mags, but now I have several that I know work that isn't an issue. I only have double feeding issues if I try and run it on 11.1v lipos.
Other than that I love it, it has been a great reliable weapon that has never let me down with good range and accuracy right out of the box.