My friend and I are both big guys. I am 6'3" and he's 6'5".
The Brownings fit us perfectly.
Like I said before, I use my 3 1/2" BPS for Geese and Turkey.
If I only had a 3" gun, I wouldn't necessarily feel under gunned though.
The 3 1/2" version gives you more pellet count in the larger shot sizes, that is the big plus to having it.
A guy could compensate by buying Bismuth, Heavyshot, or a Tungsten Polymer load, just for the Geese.
Unless you shoot lots and lots of geese, that really isn't THAT expensive given the big picture.
I use 3", 1 1/8 oz. #3 shot steel loads @ 1550 over decoys for ducks and I use #1 or BB for pass shooting.
Geese I like BBB in 1 1/2" oz. @ 1550 fps. with a 3 1/2" shell. I could probably get the same killing force using a #2 Heavyshot or Tungsten Polymer shot out of my 3" gun.
I am not trying to dissuade you from buying a 3 1/2" Citori, I am just telling you that my friend has one and he is a big buy and he even feels that the gun is a little bulky and awkward for an upland gun and so do I. If you are only wanting to use it for waterfowl, then it is probably a nicely proportioned gun. It should give you a good follow through with the up front mass. It just isn't quick pointing like I think an O/U should be.