Depends. I love sniper, so on maps where playing sniper makes sense, for suppression purposes, I will always opt for sniper.
However, I realize I am not a great sniper. Sure, I have a strange sniper rifle that is ALMOST at 7500 kills, but it has taken me forever to get there. I am sure that, for those of you that know pickledhorsefetus, he got there in one day on 2Fort.
So, I have been sticking to Soldier lately and being as offensive as I can be.
Oh, and I wouldn't through pee on Sanct if he were on fire.