IL-2 1946 questions

Okay guys, after eyeing it for some time now, I believe I want to get IL-2 1946. But I have a few questions.

First of, what kind of computer do you need to run this game?? Right now my comp runs Sh3 pretty well and Sh4 the same but not Sh5 at all.

Secondly, what is the campaign like in detail??

Third, just HOW MANY planes can be flown here??

Fourth, is the disc like Sh3?? As in I can install it and play without the disc so I can put it on multiple computer and play LAN games with my friends in the same house.

And finally, any glaring bugs or glaringly awesome features I should know??

Thanks guys