Yes, both have Kona coffee flavor notes, but they are also quite different too. The Kona Coffee Milkshake is Kona in a creamy base, the Velvet has a wider variety of notes including rum and a stronger coffee punch. 80/20 should be fine in just about anything as far as thickness goes. I haven't used a Lavatube myself, but the Vision Stone is 510 threaded and will work with just about any 510 threaded device. I don't have any coupons running currently, but I'm just about to put out the February Virgin Vapor newsletter which always includes some specials and coupons so be sure and sign up for the newsletter. I only send out 1 or 2 e-mails a month so you won't get a lot of junk...just the good stuff!