If you want them, do them.
They'll take a long time to get done, and then you have to put in work to keep them going. Don't expect them to be easy. And they'll be haggard for the first little while, but it gets better. At 15 inches you'll have decent length dreads to start off with, but it will get a lot shorter.
"You only have 6 posts, so you should probably go with the griffon, seeing that someone with such low posts would never need anything over 12 din. I mean I have just over 100 posts and ski 14 din binders, so u would have to work your way up, smell what I'm steppin' in.......... " - theNUTZ