Well, i had already steam installed, so no issues with steam here, 500mb for a demo, it is nothing special. What you guys want then? 100mb demo?
Also with DFP i had no problem with DFP gear stick thingy whatsoever, so again your fault.
Physics: Just decent, no problem.
Anyways these my opinions, full graphics maximum AI etc. runs good. Dont compare it to LFS like: oh look LFS has constant framerate, and this doesent.
Those two games has different graphics, offcourse there is different framerate.
LFS is very good simulator, no doubt about that and kudos to Scavier.
Just my 400 cents.