In that case, if you do decide to switch to letting them live together full time from the beginning, you'll need to be able to stay with them for the first couple of days. I'd also suggest starting out in a small space and giving them at least a few days before starting to extend it. Even if they're getting on well now, there's still a possibility that they'll fight over something once they're together full time (they may not, but it's a definite possibility!) so you'll need to be able to keep an eye on them. I'd also resist the temptation to rush - I did this at first, I thought it was going well so I moved them on straight away, and we ended up right back at the beginning. Now we're taking it much more slowly, which (so far, touch wood) is causing far fewer problems.
Good luck!