I'm eager to try the 5v setup on my Grand as well. Just ordered a couple of them from Randy @rtdvapor!
I've tried the dual coils on another 5v pv and I loved it so I hope it does the same for my Grands.
Right now, I'm loving Boge 2ohm cartos and dual coil cartos on my Grands. Can't seem to get the hand of atties.