RE: How dumb would it be to start flying a PTS without a trainer?
If you can get an instructor for a few lessons, do so. I wanted to go it alone myself and I'm glad I listened. Your instructor can teach you some basics that you won't necessarily learn on the sim. For example...My flight controls were not setup right and it flew awful the first flight. I'm pretty certain I would have crashed had I taken it off on my own. If you have not flown before, at least get some instruction for the first few until you know your plane flies right. It's hard to get it in the air and work out all the bugs when you really don't know how to fly it. I got some instruction and still have made a couple of bonehead moves and damaged mine when I went at it alone.