At the risk of getting involved in yet another Robbie bashing exercise, I make the following comments - as these may help someone.
I flew the first 66 in Australia, within a week of it being in Aus. Obtained one of the first endorsements for it. 5 years ago ? I have flown 3 machines on / off since then.
First thing I noticed, like others, is that when 2 up & low fuel it it feels very light. Rule number one, keep the disk loaded (thanks to many high hour pilots that told me this 10 or so years ago when I started flying helis - about ALL machines).
Second thing, the 66 is really powerful (3/4 fuel, 5 up, confined area, 30 degrees, up, up and away) and fast. 60% torque, 130 knot cruise.
One of my good mates has around 1,000 hours on one now, and we both AGREE - never fly the 66 "light". Fill it up with fuel, people, golf sticks, beer, or whatever else you can find.
Keep that disk loaded, and do not fly it at 130 knots, by yourself, in the mountains.
The 44 is quite different, after all it has that big lump of metal (the motor) in it all the time !
I hope that helps.
Arrrj
PS _ as someone else said, 2 blade helis have flown a "few" hours over the last 40 years or so !