I shot my first IDPA match a few weeks ago with my Sig P226 Elite. The first DA trigger pull wasn't a big deal since the initial targets on each stage were typically close. And any longer range shots were towards the end of the stage and single-action. I also shot my first steel match with the P226 and the initial DA trigger pull was a disadvantage on any stage where the initial target required any meaningful aiming. Having newly returned to shooting, I've found the P226 to be a challenging gun to consistently shoot accurately, giving me the perfect excuse to add a G35 to the gun safe and it is an amazing shooter so far (no DA, trigger pull is plenty quick and in general it is far easier for me to consistently shoot accurately).
In addition to the P226 feeling very intuitive and natural in my hands, the thing I love about it is that it absolutely goes bang every time I pull the trigger without fail. I own a Colt 1911 and it is a wonderful shooting gun, but in my limited match experience (only 2), it seems that folks shooting fancy single-stack 1911's are far more prone to malfunctions (which may have something to do with the dry, dusty environment here).
The net being, I think the P226 is fine for IDPA, but you may find it challenging in other types of competition.