As far as I've been able to tell, PP's anti-gun stance is simply an ass covering mechanism- not an ideological issue. Many gun related items are done via paypal, many airgun dealers take paypal, they only get restrictive on actual firearms and ammo.
I'm not fond of all of their practices, but they do some cool things- like allow one to generate one time use CC numbers for online ordering. Also one-site cc numbers for multiple use. (this requires having a debit or credit card tied to your account, which I don't at the moment, but I have used the service successfully in the past)
I've found their security to be fine, and their responses to OTHER security issues (stolen cards, stolen passwords) to be pretty decent.
I think their fee structure is a bit high, but I can't really say what their costs are.
I'd like it if you accepted paypal payments. I won't leave if you don't, just be a bit more convenient for me.