That's awesome news Steve. You four "took the poly bull by the horns," so to speak, and all that emotional stuff that seemed so scary from the swinger angle turned out to be manageable after all. From your post and description, you guys are approaching communication in exactly the right way so far. Doesn't mean you won't run into bumps in the road, but at least you all have the freedom to really open up to each other, in every way.
Polyamory isn't always an easy way to go. But in my experience and from what I've seen, it's usually very worth it and richly rewarding. So, carry on, keep reading, posting, learning, sharing. I have quite a good vibe about the future of your newborn quad.
Love means never having to say, "Put down that meat cleaver!"