Yes; I have
I travelled from Australia to England and spent 2 nights at a FTers place.
I had known this person for less an a year. I had been speaking to them on MSN, but had never spoken on the phone.

I spoke to someone online probably not FTer; and shared a hotel room with them and I had only known them for a week.

It was ok. I never met any of these people before I stayed with them.

Is that supposed to be a problem, seems like you people are so cautious.