H500, not sure if you've operated a G2 and a R22 in your company but it's no secret that the operational/running cost of a G2 is a lot higher than a R22. I might even dare to say it sits closer to the running cost of a R44.
Unless you don't count insurance, depreciation etc and purely look at the service interval costs, then I'm not sure since I don't have all the data for that. But counting everything from purchase, depreciation, insurance, maintenance, fuel, oil etc, then the G2 will empty your bank account quicker than the R22....