I have had some problems with 2checkout also, no major problems, but well I'm guilty of still using them. It seems like ever scince they updated their tos and changed providers everything has been going all down hill with them. I think the only real safe way to go is with a real merchant account.
By the way I moved your post to the online business forum incase you didn't notice. It was just created today and needed a post it in it.
