In current state of advancement in FSX addons, when talking about technicalities nothing seems to be impossible, it only takes time and effort, and that's what A2A proven this far. The problem with both F-104 and F-4, and all other jets of the "century series" is, the amount of those speed bumps is pretty much as high as one can get without venturing into the FBW area. Lot's of complicated systems, pneumatic, hydraulic, electrical, jet engines and avionics. It will be great to run U-2 intercept training missions in Zipper, and taking the Rhino downtown from the deck of USS Saratoga, but it will take a long time before that happens.
Everything can be done right, and I have trust in A2A that it will be done that way. Although I do think that going for the Rhino, and Zipper is quite a high jump from WW2 props. I do wonder if it wouldn't be wiser to go for the F-86/FJ-4 first instead.
I would respectfully suggest that any "fears" one might have about reproducing the systems and flight model behaviors of both the F4 and the 104 using the infrastructure available within FSX are misplaced.
There is nothing that "abnormal" about either the aerodynamics or the internal systems involved with these aircraft really.
I remember dealing with just this issue back in FS2004 as an adviser to Cloud9 when they were doing their F4 and 104. Even back then, and without the benefit of Accusim, what Alberto Sangalli and his designers did with both these aircraft was remarkable.
With the advent of Accusim into the design equation, I would project that when these 2 aircraft come on line rolling out of the A2A hangar, they will represent not only museum quality replicas of both airplanes but will also present to the end user a product in the simulator that can literally be used in an audio-visual checkout program for either airplane as an introductory tool for pilots training to fly either one.
As an ex-instructor and check pilot flying warbirds myself, I wouldn't hesitate to use anything thus far produced with Accusim in a check out program for the aircraft represented..........trust me...........Accusim changes everything!