Hello. I own both a P245 and a Glock 30, not the G36. They are both fine pistols. Here's the differences:
The Glock has a single trigger pull weight and a completely different action than the Sig DA/SA. The Sig DA is SMOOTH, but is a different trigger pull than the SA mode. I'd shoot both and decide which action I like FIRST. Some people hate the Glock trigger, but with practice you can shoot well with both...
The bore axis on the Sig is higher than on my G30, and the muzzle jump and recoil is greater, in my opinion, with the Sig than with the G30. Don't know how the G36 fares in this comparison...
The Sig is a beautiful gun. The Glock looks like a tool, and has a much more durable finish. If you are going to carry the gun all day, the Glock will probably show less wear than the Sig.
The Sig is the most accurate of the two, without a doubt.
If you get the Sig, get the Nickle version. The finish is far more durable than the standard Sig finish which wears quickly with holster use.
The Sig has the most comfortable grip for ME.
That being said, my carry pistol is the G27. 10+1 capacity, small package, very concealable, and more accurate (mine, anyway) than the G30. Hope this helps.