The P226 BW is gonna be a great gun, as are all SIG pistols. But you'll have to try one out to see if it's what you really want. Since you asked how it compares to other platforms, the only real way to find out is to fire a bunch from different manufacturers. All platforms will feel differently, point differently, handle differently, shoot differently, have different triggers, different actions etc... What you'll have to do is pinpoint what you want in a pistol and go from there.
If you want DA/SA action, the SIG is one of the best. SIGs usually have clean triggers out of the box. They're accurate and easy to shoot. The BW grips are a little thick, I'd probably put the factory plastic grips for shooting, or Hogue recheckered grips since they feel more comfortable to me. Don't stop at the SIG however, keep shopping around and see if there are other platforms that may fit you better. For 9mm options take a look at:
HK USP
HK P2000
Glock 17/ G34
CZ-75
Beretta 92FS
S&W M&P
XD9
All those would be quite different from what you already own. They're all excellent platforms that deserve a consideration.