Stinger, I sparayed a piece of plastic about a month ago and buffed half of it to a high sheen. I left the other half unbuffed. Two nights ago I sprayed some of both halves with Future and let it dry a few hours. The unbuffed half seemed to change slighly and look a bit more rough. The buffed half however seemed to have only got a bit more glossy. I then toke two pieces of tape, one covering the sealed and unsealed side of the unbuffed paint and the other covering the sealed and unsealed side of the buffed paint. I pushed them down good. As expected, the paint on the unsealed sides came off onto the tape. Not all mind you, just enough to show on the tape. On the Future sides however, there was none on the tape whatsoever.
I'm planning to try this same test again using the Metalizer sealer and see what happens. But I can tell you that, right now, I'm planning to use Future on top of the Metelizer and then after it has complelty dried, mask off sections I need as normal. According to my test, I shouldn't have a problem.
Oh, I'd also like to add that no primer of any kind was used. In fact, the plastic model parts I used were in no way prepared before my tests.