I will tell you that I love my SC250. I will also tell you I'm new to two-wheels though. As for your reasons:
1. If you aren't too worried about loosing money when you sell it then that's not too big of a reason.
2. The AF1 forum http://www.apriliaforum.com/forums/f...io-150cc-350cc
has some pretty good stuff along with the actual store, AF1 Racing, which has been great with parts and their customer service is spot-on. http://www.af1racing.com/store/Scrip...dCategory=1111
3. That goes back to #1 in my opinion, if you can afford to change bikes regularly then do it; It's a wonderful bike.
4. I just installed the Puig and havent' had a chance to really
give it a go. It does blow wind right into my helmet so it's loud. I do plan on playing a little with the angle and that sort of thing to see if it helps.
So, to answer you true question: Yes be afraid if you are concerned about the $ and Yes be afraid if the windsreen is really a deal breaker. That being said, I think you would really regret not knowing how great a bike the SC250 really is.