Hi there Cyclic Flare, you may have a problem moving your R44 over grass especially if you are using the standard factory supplied ground handling wheels as the vast majority of the weight falls on those wheels. Unless the ground is really smooth and rock hard the wheels will just sink in, no matter what electric tow truck you are using. I believe thqat there is a Canadian company who make oversize balloon tyre wheels for use on soft ground. I saw them at Helitech but can't recall the name.
I have a HeliMover and it is a great piece of machinery which makes life so easy. One of it's really useful features is that, unlike the RHC factory item, is that whole thing will swivel between the skids making manoeuvring a breeze. It's also the most reliable and with the current £/$US exchange rate the best price too.
Check out the link above.