The other thing to think about is that (I think) FSDT and Imaginesim both have trial versions, so you could test both sceneries without any purchase to see which one works better for you. There are always complaints about FSDT's COUATL program, which controls the functions of their airports and is kind of a DRM also, but I have never had any real issues. I actually don't have any Imaginesim airports, but I have a few FSDT airports now and they are all really excellent quality, and good on performance too, especially considering the size of the airports.