WOW, GUYS I am going to totally dissagree here, I personally feel G2 sucks, well ok, FMS is the best I've seen and yes it is totally adjustable from gyro sensitivity, to thrust, head speed, cylic control movement, rotor blade weight and lenght, etc, etc.etc. now granted as the free download version it is very basic, but with a few simple upgrades it is a equal to G2 but still free but with 2 main advantages. 1 it will run on a BASIC COMPUTER with no problem, 2 you get better depth perception on the heli..
their are 2 disavantages though, 1 you can't see the individual blades of grass and crowds of people, 2 you can not do autorotations real well.

so for $200 g2 gives auto's and grass.
free fms gives some awsome fields with the limbo, pilon racing, competition training fields, some awsome graphics on the heli itself on mine you can see the radio through the canopy (sweet)
Most of the upgrades are in Japanese, but I got G2 and have tossed it in the can, and yesterday, my buddy tried it for the first time, he also had G2, well, he took my copy home and is selling his G2 on ebay. G2 is still a good sim but just not worth the $$$ when you consider you can get the advanced versions of FMS free, but most people just don't know it's out their