Atheists have better sex than theists?

Who has better sex, atheists or theists? According to this piece, atheists have better sex because they are less likely to feel guilty about it:

Atheists have far better sex lives than religious people who are plagued with guilt  during intercourse and for weeks afterwards, researchers have found.
A study discovered that non-believers are more willing to discuss sexual fantasies and are more satisfied with their experiences

If this is true, it certainly has implications for sex therapy. I doubt that this means that people will have to stop being religious, but perhaps spirituality and religion will need to become more active topics of discussion in therapy. What would be interesting follow-up research--what separates those who are religious and have good sex from those who are religious and do not have good sex? My suspicion (completely unscientific speculation!) is that the factors that equal good sex in the religious are not the same as those that equal good sex in atheists.

Read more here.