[Guest]

Not that I am aware of (speaking of which, such a topic would be a good idea. In the summer I may have to write such an article up....)

But basically HSFX 4.1 is a mod pack (which used JSGME)

And Utltrapack 2.01 is HSFX-4.1 but with more mods and edited FM's on some planes (with a switcher to switch back to HSFX defaults IIRC)
SO in a nutshell that's it