You can have different religious views to a partner and make it work: my wife is Christian and I'm agnostic, and we agree to respect each other's views. But this wouldn't work with an obsessive Christian, who will always be trying to convert a non-believer to save their soul. The other problem is that Christianity is anti-sex, so there's no possibility of sex before marriage. Even after marriage, Christian sexual guilt can often lead to a plain, boring and vanilla sex life.
My wife was waiting for marriage, but we ended up having sex anyway (her first time). It was okay, as you'd expect for her first time. After a while there were a few too many sexual boundaries for my liking, so we had to deal with those. She enjoyed sex in her own way, and she always was in the mood for me, but we needed to build some variety into our sex life. We eventually got there, but it was hard work.
On the whole, I would steer clear of a Christian believer.