Interesting news.
I agree with a lot of what Newmanix said.
With what has happened with the Intersim fellows over the past 6 months or however long it has been since they surfaced then disappeared and now surfaced again, it's hard to keep faith in their project. For all we know, another problem/issue could arise causing them to disappear again and not release the airport.
In addition, at this point I would prefer to purchase an FSDT version for the following reasons.
a. You don't have to worry about FSDT disappearing/closing if you need help or support
b. You can be assured that the FSDT version will be as optimized as possible for performance without having to cut detail using the complexity/density slider
c. FSDT is a step ahead of others with their on going developement/techniques in the use of shaders and textures ie. KDFW and what's planned for KLAX
d. The "Miami City" that they are going to release with the airport is currently available to anyone as freeware thru Toni Hiltuni
Just to be clear I am not saying anything bad about Junior Puente since I had spoke to him a few times in the past and he seems to be a nice fellow, but when the project is an on again - off again type of thing, its really hard to keep faith in when or if it will ever see the light of day. It's also kind of weird that Intersim has "surfaced" again now that FSDT has said that they will do KMIA. What if FSDT hadn't come out and said they would do KMIA? Would Intersim have come to life again?
Personally, at this point I hope Umberto and staff continue to do KMIA, but if they decide to cancel on this news, I guess I will have no other choice other than to buy the Intersim studio version since I have really been wanting an FSX version of KMIA for a long time. I don't have any of their other airports so I can't saw how good or bad they look or perform, but having the majority of FSDT's work I know that KMIA would be an excellent rendidtion that will perform well.
It will be interesting to see what Umberto has to say after reading this news.