The gun in question is a
Sig P226 Combat, with plans for a nightstand gun. It may also become a USPSA gun... Or hell, a varmint gun!
Anyway, the Leupold Deltapoint is compatible with the P226 without modifying the slide. Unfortunately, the Trijicon RMR is not compatible unless I have the slide milled.

If I get the Deltapoint, I feel I would still need to add a flashlight, so that's another expense. I'm leaning towards a
Viridian X5L light/laser to supplement the Deltapoint.
If I do not get the Deltapoint, I would probably get a
Surefire light/laser.
What would yall do?