Notes:

With cutouts from

I think it is noteworthy since not only their voices are (or at least used to, some complain) very distinct, but also it's the only VA who voices two mercs in-game.

Well, technically Dennis Bateman also dubs two (Spy, Pyro), but Pyro only has basic speech that's muffled on purpose, so I guess that Gary has a bigger workload than everybody else.