Greg, I would suggest that you get a 9mm bull
barrel and a .40S&W barrel. I also own the
P229/357SIG since it's introduction back in 1994.
My two switch out barrels came from ErvIII at
BarSto. Although SigArms says, no-no-no on
this arrangement, I have never had any problems
whatsoever. By the way, I use the same magazines
for all three calibers. Nines and 40's are cheaper
to shoot vs. the 357SIG round. But damn, ain't it
a hoot to shoot that round. BOOM! ZING! Tain't
nothing faster other than Superman.
Ed