New to vaping (XROS 5, ex 6–7 cigs/day) — should I use 0.6 or 0.8 ohm, and what non-sweet flavours (e.g. caramel tobacco) would you recommend?

I have recently moved from tobacco to vaping. Used to smoke 6-7 cigs a day. Got myself the XROS 5. Quite confused. Should I use the 0.6 ohm or the 0.8ohm and what are the liquids you recommend. I would prefer a not too sweet flavour and heard good things about Caramel tobacco etc. Any help would be appreciated. A noob here.