Ooops my bad, everything you say is absolute veritas. P228 was the original M11. Sig reintroduced the M11A1 in the last 18-24 months but it was a commercial version and essentially a P229. To the best of my knowledge none of these P229A1s have been procured by the government. I had a P229 in 9mm back when the P229 was first introduced and it was a contract overrun for some Middle Eastern Military Contract (I later sold the gun and it was incompatible with the 40 barrel). You are correct the P229 was originally designed for the .40 and was marketed as the first pistol designed around that caliber by anyone according to Sig a totally new platform, the S&W 4006 being nothing more than a beefed up 5906 (whatever, advertising hype is hype).
Interestingly though, as far as frame incompatibility goes I don't doubt the veracity of your claim but I will say that my current P229 has 3 barrels: 40, 357 Sig, and a Bar Sto 9mm drop in. (absolutely no problems with that either, my P229 is 1997 vintage, I understand some of the later ones need fitting do to some desgin changes and tolerances) As far as 9mm mags go, I have original pre-ban P228 mags which I have no trouble with in the pistol as well as one marked P229 also pre-ban. These are 13 rounders (I realize the new 9mm Free State or standard version mags are now 15 rounds).
I would point out that the MSP used the later Model P226 which had the stainless slides, not the original sheet metal ones, and it was regularly carried as an off duty and CCW by non detective personnel who were authorized to be in civilian clothes. I personally have had no problems carrying the P229 CCW on and off for the last 9 or 10 years. Maybe its a big deal for some, but everyone is different. YMMV. I think body type and belt selection factor into it.
One would think that the P228 having a sheet metal slide would balance differently. Thanks for catching me on that one.
It doesn't have a rail so I use something else for home defense.
