Are you serious? Are you also very young? If you care about someone you wont really care about who they slept with in their past or what they did before you, it's what happens when they are with you and after that matter. There is nothing wrong with some experience because you might find out later she is either not interested in sex or LOUSY at it or wont do certain things you might like. Talking about it and doing it are two different things.
If you dont think sex is VERY important in marriage you will someday have a rude awakening. It may not be everything and if you only have sex in common it wont last either.
I for one would never be with a woman who didnt like to give and receive oral. My current GF had never had or given oral. She was very unsure about how to react or what to do but after a few lessons she started to loosen up and now she LOVES it, getting and giving and she is getting pretty darn good...
I have been with women who where very skilled before I meet them also due to practice. Never bothered me one bit. Jealousy is a bad thing and will kill any relationship.