I have been using the nautilus mini for a couple of weeks now on the mvp 2.0 at 11 watts no problem, no burnt taste. I just got the 20 watt and when I push it above say 12 I start to get the burnt taste, I will try tightening up the air flow, if that doesn't work I will try different juice once or a new coil. On a side note can the bvc heads be cleaned?
kinda sounds like you answered your own question...
a 1.8Ω is about 9W max, for me (burnt)
you need to seek a 1.6Ω, perhaps a LITTLE better performance
I use the LITTLE bvc coils, and they deteriorate somewhat if you dry burn them
kinda like the ceramic fiber coil starts to crumble
- http://www.discountvapers.com/nautilus-replacement-coils-bvc-1-6ohms-5-pack/