I have been using 15mg diy juice on my nimbus clone since I got it a month back, recently quit smoking so I need the higher nic levels. I make my juice at 70vg30pg.
I tried many different builds, different wicks etc to figure out maximum flavor methods. There is a few things that effect the flavor, how hard you inhale, how wet your wick is, and how your coil resistance is matched to your available airflow.
Maybe because I just quit smoking, but for me even with some 18mg mostly pg liquid the throat hit wasn't a big deal. Although the 24mg Aroma GI Joe I just got has a Wicked good throat hit I must admit!
So yesterday I drilled the airholes out to 2x 2mm holes on each side, with a 1ohm build. Now even 100% VG juice is harsh! My guess is the coil can't keep up with the high airflow...