I'm an instrument pilot working on commercial and I have never found it too useful for real life training, I could do approaches for Illinois, Indiana, Ohio and Wisconsin as those are the approach plates that I actually have, but other than that I'd just a guess as to what your DH or MDA is on an appraoch. I also wish they had an Piper Arrow in there, as that's what I'm flying now.
I use a logitech joystick that has rudder build in, and MTpilot, you need to turn off the autorudder. With the extra 300 and the new p-51 you need a lot of rudder to make a coordinated turn, and just to climb out full power.. especially the p-51 I think they listed it like 2000hp with the twin turbo setup. It's crazy, flying along ~150in Hg and 2500rpm.
So it's large shortcomings to me are, it needs the approach plates for all of the airports, it allready gives jeppesen charts for the missions so why not any other airports? Next it needs power charts and such for all the aircraft, heck some don't even have a reference for Vy, V1,R,2 etc. How do you push the limits without Vspeeds and performace charts.
Finally on the F-18, I know these stats are true: Climg rate: 45,000ft/min, service ceiling ~50,000, top speed Mach 1.8. The F-18 in the game can do none of those.
My computer is a Core2duo 4400 running 2.67Ghz with a Nvidia 6600OC and 1.5Gb DDR400. Runs ~30fps on mostly high settings.