I'd suggest not moving in right away, but if you're going to, it would be smart to discuss ahead of time what the back up plans are for each of you if it doesn't work out, if one or more of you decided co-habitating is not working, hell, YOU might even find that friendship living with R was fine, but once it's a romantic relationship there are things that bother you about doing so. He may find "trying out" a V doesn't work.
If R is dating other people, talking ahead about how you all see your shared home being utilized or not for dates, obviously talking about who is sleeping where when, and I think it's even MORE important to have it clear on who is doing what chores in a case like this, so irritation about roommate stuff doesn't seem bigger than normal because of any problems going on with the poly setup.
I guess what I think the important thing is, if you want it to be an equalish V and you all live together, the ability to discuss and decide all these things as a group is going to be your best friend.
Happiness will never come to those who fail to appreciate what they already have.