Ditto on the SR9C and didn't know that the M&P had ambi slide release, way cool!!!! We're I a lefty, I'd look seriously at those two first. Glocks are like Legos, mix and match, plug and play, but I never support guns that don't have safeties, they're detrimental to the firearms community and an accident looking for a place to happen.
Bersa does something like this...
BERSA THUN45UCSS 45 ULTCMP 7RD SS