Glock.
In extreme environments that can rust-out even stainless steel, (Dont laugh, I just saw this in April '01), I'd trust the Glock & it's polymer frame.
Glocks are more popular in in SE Asia than Berettas -even though Berettas are still standardised military issue in several countries there.
The polymer frame on Glocks also stand up to extreme cold temperatures -just in case you get sent to Siberia.
Stop oiling your Beretta, throw some sand into the cut-away slide and see if it still works!