[justin66]

> Why bother with the F104? Feels like you'd want

Both the F-104 and Mig-25 are on the record as being very high-performance, record-setting zoom climb machines. There are some other planes out there that can do a similar job. I believe the F-4, oddly enough, set some records in that area using a slightly modified engine setup (water injection).

The F-15 would sort of be the textbook platform for this: there's a reason they used it to launch ASAT missiles, and you could fly one today with more powerful engines than that eighties-era F-15. On the other hand, part of Starfighter's appeal is that they can do these launches relatively cheaply.

> Mach 3.2 vs 2.0 for the F104

You're comparing a pretty desperate MiG-25 speed to the pursuit speed in the F-104's flight manual. Speed in level flight isn't really the issue here anyhow.

EDIT: Starfighters indicates their Italian F-104s will do Mach 2.2 while climbing: http://www.starfighters.net/fleet/

Lots of good stuff on that page.