You've got the gear you need, now you just the gun. The ultimate decision is up to you, my advice would be to try both. Assuming you're renting tippman 98 customs, you've had experience with mechanical markers. Go to a field or a shop and see if they will let you try both pump and electro, especially pump, it's a love/hate relationship for many. You can't go wrong either way, it's much easier to switch from pump to electro because you need to be more tactical and skilled to be successful with a pump
. Goodluck either way, PS if you've got nice gear so far, top it off with a nice gun. Buy nice or buy twice. I've never used the KP3 but I have used the empire sniper before and it shoots like a dream, and can be found used with a barrel kit here on PBN in the B/S/T section for just a little more if not the same price as the KP3, not saying the KP3 is bad, I just know the sniper is great and in others opinions it's nicer.