I have only been with my FI and hes only been with me, we have been together nearly 8 years....I have wondered what it would be like and i'm sure he has too, its totally natural.  plus we have eachother trained to what we like in bed so i dont think it could get much better than what we already have together, it took alot of practice but its mindblowing now so were good.

lol great answer angle. could'nt have said it better myself! :)

See, my FI is the 4th, but I really only condsider him my first, because 2 of them were drunken one night stands and my ex was only a one minute man. LOL.  I can't help but to feel jelous or sad(I can't really describe the feeling) because FI has been with many people before me and he has also done a lot more sexually then i have.  He is 9 years older then me though.  I just sometimes wish that I had more experience.  I know that he loves me, but I sometimes can't help but to wonder how I measure up to his past.

very natural if both of you are open mind.

That is absolutely normal to think about!! Of course, dont' act on it!