I normally use RBAs and RDAs, but I got both the Nautilus as Ind the BVC coils on Monday. I have been through several tanks so far and I love these. I personally haven't tried to clean a head. If I want a new flavor, I just pick something similar to what I had in it before, i.e. lemon flavors. Zero issues so far. I got the coils from My Vapor Store.
For me, the mini wouldn't cut it as I would be filling it too much,. I do want to purchase a 2nd full-sized one, however.