That is no Mutation X v4.
Google that one for yourself.
If chasing clouds, I definitely recommend any of the Doge's, v1 and v2, made by Congrevape if you want an authentic. Or any of the actual Mutation RDAs, known for their very specific style airslots. Getting a clone of these would be up to yourself. I find myself wanting the Mutation X v4 now since it has 4 post holes. Three post hole decks work but 4 posts would make like a bit easier for dual coil builds.
I have 3 Fave RDAs;
El Cabron
Twisted Messes
13 Heavens & 9 Hells
All made by CompVape.
lots of stuff on eBay too if you can't wait that long.Velocity is pretty good, but I still like my Baal better with the wide cap. I was considering the Mutation X v4 before I saw the Velocity.
Any of those have deep juice wells and lots of holes for the deep lung hits. You could get the Baal, Derringer, Velocity, and Mutation X v4 clones from somewhere like Fasttech for $40-50 for all 4 of you don't mind waiting a few weeks.
Its actually made by CompVape. They just added a center post block to the El Cabron and put a different logo on the AFC. But you are right, its a good rda.Twisted messes rda is my favorite rda lately. Made by a great guy and builder too.