I sold my Turkish MP5K clone in favor of an APC9 Pro that takes Glock mags. Controls are fully ambi, reliability is 100%, and the ergos aren't frustrating like the MP5.

When I sold the MP5K it felt like breaking up from a bad relationship, everything that frustrated me just came boiling out. The APC9 is so much nicer. People like to wax poetic about the recoil being so much smoother on the MP5 series, but I can't really tell a difference.