I can't tell you about 0.6Ω specifically, but I'm running a 0.5Ω in one Grand right now and it's wonderful... except my wife thinks it fogs up the family room too much. My other Grand, the daily driver, runs 0.7-0.8Ω (the latter right now) and it is also wonderful, without the fog problem. The former is better than any 60 ring gauge cigar I've smoked, while the latter is about on par with them. I think your 0.6Ω coil should fall somewhere between. It's at the point where you'd get more real mAH out of a 1600 mAH (higher discharge rating) AW IMR than a 2000, and it may also be where you want to open the RM2 air hole from 1.2mm to 1.3 or 1.4 (at the most). I hope this helps.