I always think this: "Names are cute when a kid is kid.........but how is that sucker gonna look on a business card? A job application?"
If you want to name the kid Davan, that's cool. But maybe make it a middle name. And if your name is Christopher or Stephen or something more normal, run with that as a first name.
As a kid you can call him Davan to distinguish the two of you. But if he hates it at 23 he can go with his first name.
We did this with "James Thoreau" (Options include James, Jamey, JT, Thoreau). See, I got to give him a cool middle name and a sane, responsible, first one. And if we have another boy we're going with "Theordore Wesley" (This opens up Theodore, Ted, Theo, Teddy, Wesley, and Wes).
What do you call a kid whose name is Davan? It means he's always stuck with Davan (well, maybe "Dave".........hmmmm........). You certainly can't call him "Van" or "Davino" or anything.
Cute, cool, nifty names are nice for children but they can suck for adults. Give your kid a name that doesn't make him sound like a perpetual five year old.