Yeah it is more or less the same underneath.
The trench coat should cover it up though. The only real exposed part is his chest and that has diffeerent armor over it.
It's either this costume or the Grey Fox one, but honestly I think Mr. Kojima wouldn't want to put Grey Fox's image in this game.
I really wouldn't want the Sombrero/Poncho outfit (even though that and Suit Raiden are most likely).
I have never played through MGR Revengence, so maybe It just doesn't appeal to me like it does for you guys.