AMT/Round2/MPC are all basically the same company as far as models
If it has the Aluminum engines than it sounds like the 1/48 kit (aka 22 kit"). It even goes as far as copying the filming model cockpit and pilots. It also has springs with metal rods for the landing gear ( although there is too much tension on the springs)
That is a great deal as the price is less the the MSRP of the engine bell upgrade alone
That is a great kit and fairly accurate to one of the filming models ( I forget which one though)
I think the biggest thing to clarify is if this is the original/re-released "1.72" (which is really more like 1/100 and is around 10") tooling vs the re-tooled 1/72 kit aka (14" eagle)
the old box scale kit had a re-release and had some fancy package stuff added, but is a dud of a kit and is inaccurate shape wise, as well as having crappy detail. The cages are even solid blocks. It is a ton of work to accurize and by the time you are done you will have nearly no original kit parts left. That price is way too much for that kit regardless of what else is thrown in
the recent 1/72 14" version on the other hand is a beautifully scaled down version of the 1/48 kit and is a great kit on it's own. The MSRP on that kit with an aluminum upgrade (not sure if they did an official set or that is a third party one) still make it a decent deal
Although unlike the big brother, there is no cockpit interior IIRC