I've got one red 507C on a P-10F and really like it so far. I use the small dot and leave the sight in auto on-off mode, since this is a carry/night stand pistol as well as my plastic bullseye gun. I have 3 Burris Fast Fire 3 sights that have been fine, no problems at all. But the switches are difficult and there aren't enough dot intensity settings for me, compared to the Holosun. If the 507C holds up, I will probably get one for my P-10C as well. It has a Burris on it right now, with a tall front sight, so I don't leave the Burris turned on. Not sure if the tight fit from CGW on the P-10C slide for the Burris will allow a swap to the Holosun without some machining, however.
Hope the green Holosun works out.
Joe