what coils did you make in those Super-x? nanocoils? j/k.
The point is more wraps with lower gauge wire will achieve exactly the same as fewer with higher gauge. There are important things to consider if you switch from cartos to RBAs:
1) Rba's seem to "hit" harder - so you might need to go a little higher than 3 Ohms
2) Get a multimeter and make certain you measure all your coils before you use them in anything. If you don't, you risk batteries going postal and your device being ruined by a short.
Some people that make the same coils again and again, super-x perhaps, can hit the same values time after time. You cannot. i cannot. Use the meter.
Good luck and btw an RM2 is about the easiest thing in the world to recoil and about the hardest to short
T