I'm using the 0.8 coil MTL. I was previously using an aspire favostix at 10 watts with 50:50 6 mg juice. I had to take a long draw on that to get a decent throat hit. With the XR I don't have to take as long a draw, but I find the vape a bit warm and the throat hit (sometimes) a bit disappointing. I've tried both air flows. I'm wondering if I should use the 1.2 coil? I wasn't impressed with the flavour on the favostix but I can't say the XR is much better in that respect. I've tried several different juices all the way up to 50 mg nic salt and nothing really impresses. That said, it's a beautiful piece of kit and so easy to use but, so far, I'm disappointed with the experience. I was also a bit perturbed to read a review where the reviewer stated he was getting around 10 ml of juice per coil (he seemed impressed with this ???). I go through almost 10 ml of juice a day. Surely, I don't need a new coil every day? I was getting a couple of weeks out of the aspire coils.
Update. For the last few weeks I've been using 1.2 regular coils and this is more like the MTL vape I'm used to. The flavour seems better and I can even control the degree of the throat hit. Any inconsistency in the coils or battery strength can usually be overcome by switching between the easier or more restricted air flow. I'm starting to love this device. I've got 2 kits and a total of 14 pods that I fill all at once so I can just switch the pod when it's running dry.