For the Fuel Question. The Best fuel for the YS 170DZ is 30% Cool Power. Also if you dont like the smoke trail from the Regular 30% you can try morgans LS (low Smoke) version of their 30%. I know of a few people that fly the LS fuel and have had no trouble with it.

Also, if you can, try and get the CDI conversion kit for the 170. The CDI kit will let you run a lot leaner needle and in turn save you fuel and allow a longer flight time. (added about 6 minutes for me)
The CDI kit also allows you to run a 19x11 prop which IMHO is the best prop for the BMV3.

hope this helps.