So setting aside the $499 or $9.95 per month layout, what's holding it back?
Probaby the fact that:
a. a lot of people might not even know about it, speaking more of the non-enthusiast general user who doesn't spend time reading the forums or buying addons
b. misconceptions that the general public is not allowed to buy it
c. unknowns about what FSX addons will or wont work with it, and if the said FSX addon will work with P3D, how to install that addon without a proper 3PD installer
d. the fact that some people don't want to shell out the $499 or $10 per month
e. some people are happy enough with the performance of FSX that they dont feel the need.
For me personally, I haven't really investigated it too much mainly because of the addon compatibility questions and the fact that I am generally happy with FSX as it stands. That doesn't mean that I wouldn't like to get more performance or better looks out FSX, but until more and more of use FSX users start switching to P3D and can give some reports on if performance is that much better and if there are generally no problems using the majority of leading FSX addons, ie, FSDT, FT, PMDG, REX, etc., then I will just sit tight.
I must say that I wouldn't mind spending the $10 a month if it was truely a much better product. Plus I like the fact that the P3D guys are constantly working on making the product better rather than just launching it, then provinding a few SP's then being done with it until the next version come out, like FSX or FS9.
I imagine that only time will tell. We still have Flight to evaluate if or when it comes to market. There have been some unsubstanciated rumors lately that Flight has been cancelled, while I don't belive it until I get official word from MS, I suppose that its not entirely impossible that it could be cancelled or put on hold, in which case it migh make a more compelling argument to take a closer look at P3D. The fact that ORBX is already working on it would lead me to believe that other leading developers like FSDt could be as well or might be in the future.