If I spray paint PLA will it last outside or am I better printing in ABS?

I am designing a cctv camera housing for the tenvis iprobot 3, when I print it in abs it warps due to it being so large but do not have this problem when its printed in pla.
I have heard that pla will degrade outside, I was just wondering how long it takes and if there is a way e.g. painting that I can stop it.

Many Thanks
Colin

I Probot 3 Case.jpg