Tru Flight
I think if you search around you will see a previous thread on this sim.
I bought mine at Toledo at the Minature booth I was told it had better physics than any other helo program. I had to buy a new computer to run it but I was planning to buy a new puter so no big deal there. The copyright protection is in the cable which took me almost 6 months to get fixed after many frustruating hours trouble shooting the problem.
They claim I am the only person who has had this problem.
Minature really didn't provibe any product support, had to deal with the guys in England.
Once up and running It is quite good. Very realistic. I practiced my nose in hover for a few hours and went out and managed to do it. So the program paid for itself right away.
I have a little experience with other sims but for helos it is the best I have seen.
Sparky