The P226 is an outstanding pistol, with no special caveats attached to it. They are uniformly accurate, totally reliable, and very well made.
Because it's been around since the mid-1980s, it's easy to get reasonably priced pre-ban 15-round magazines for it. Every holster maker has leather for it in their inventory. The P226 is to 9mm pistols what the P220 is to .45s...a great design with an excellent reputation, which can hold its own against any other pistol in its class in every respect.
The P226 does not come with light rails, so you're limited to lights which bolt to the mag bottom or the trigger guard. Lasermax makes a guide rod laser for the P226, if that's your cup of tea.
I think you made a great choice. I have a P226 on my belt as I type this, so I am pretty biased, but there aren't too many people who have anything bad to say about the P-series SIGs in general, and the P226 in particular.