I think you're wise to know your own values and set some boundaries on when you're willing to be intimate with someone.
How sad that this world has become one where the mention of someone's promiscuity in another thread brings on finger wagging and warnings not to 'be judgmental,' yet mention of wanting to know someone well and trust them and know the relationship is solid before having sex brings on a number of judgments.
If we're going to be non-judgmental, we need to be non-judgmental. Or did I mistake the meaning of the word? Does it really mean, "You may not judge me or my values, but I may judge you?"