Hi, I'm thinking about getting a Steam Crave Aromamizer Plus v2 and stumbled over this forum post. The tank on that picture there has knurling on the top cap. My question: is this maybe an early prototype that they did send out to reviewers or does the top cap from v1 (with knerling) fit on the newer v2 (without knerling)? What other parts are also interchangeable between the two tanks other then the build deck it self?