First of all, welcome to the site.
Well, I'm not sure what you mean by the aftertaste. Any
juice I've tried leaves some aftertaste or other. As for the burnt taste, it's probably that your atomizer (whether a straight atomizer or the coil built into a cartomizer) isn't getting enough liquid, and is overheating and burning your wick and/or filler material (if using a carto).
I can't say what the best of anything is, as that varies from person to person, but I'll tell you what works for me. The
tank type I like comes from
Mom and Pop Vapor Shop; it's the basis for the tanks I build for myself.
In those tanks I use Boge 2.0 ohm stainless steel cartomizers which I punch two holes in using a
tapping saddle & valve (the brass Watts one) from Home Depot .
Hope this helps.
EDIT: Fixed links.
Another EDIT:
What are you using now that gives you the burnt & plasticky taste? That might help us diagnose what's wrong.