LOL, I just checked the starting date...hell, I had most of my hair and all of my teeth when this thread started....however....I'll join in!
We've got 'em both. Son #2's 92FS has way over 5000 rounds through it and been in use since '95 with nary a broken part. It's as accurate as the day it rolled off the assembly line with our handloads, too. My son, a former Marine MP shoots it extremely well and has no problem with it's very full, rounded grip. For me, it's like trying to hold the fat end of a baseball bat...I just can't get around to liking the grip feel.
We both also shoot a number of double column Sigs as well, and have no problem with them as to grip feel. None have given us any trouble with parts breakage either and are a bit more accurate than the 92 FS for that critical DA first shot. To my hand, the Sig's are a bit thinner through the grip than the Beretta.
Without starting a caliber war, if you're enamored with the 9mm round, either will do, but the Sig's offer a bit more choice if you want something bigger and, in my view, better...357Sig, 40, and 45 are all readily available in Sig's lineup. I don't know if the 92 has the option of different calibers.
As to military acceptance, I'm one of those who found the choice of the 92 perplexing....I'd have preferred one of our domestic companies, and would also have kept the .45. Politics with our supposed allies certainly had something to do with the choice...YMMv, but I don't care. That said, the gun has worked out OK, I guess, but it's bigger than the 1911 and for females and small handed guys, it's more than a handful. Again, YMMv. About the only part of the switch over from the 1911, that I liked was the new holster and web belt assembly...I really like that Bianchi made holster (I think) rig for military use.
Lastly sights: Get tritium sights if you're seriously thinking of using the gun for defense after sundown....Again, I don't know if the 92 has that option, but all the Sigs do, and those sights are every bit as precise as a plain black post or the three painted-dots variety.
Were it me, I'd get the 226 if limited to the OP's choices...it's a great pistol, a bit smaller in the hand than the 92, and with a sterling LEO and Military Special Forces reputation. And get it in .40, a more substantial caliber with a far greater bullet weight selection. But a better choice is a P229, a substantially better concealment gun if you need to take it off the range, and is equally accurate (in my hands) as either the 92 or the 226. My version is the M11A1, a P229 in all but name, and chambered in that diminutive 9mm caliber.
YMMv, Rod