BUT there is 0 reason to use a VW in a group. When you get higher level you can spec into fel Synergy and your imp wont die all the time.
That said, for now i Really think demo is the spec for you. Its alot like destro more nukes but you also get a felguard (which is alot more durable than any demon save voidwalker) and you can have fel syn right now.
Yes once raiding you ideally should pet swap with felpuppy as needed but for 5mans you can ignore that if you want and just use Felguard.