This is the search URL I am using for Robinson:
FAA Registry - Aircraft - Make / Model Inquiry
That seems OK.
But, damn, the initial search I used for Bell was not a good one
In redoing this I tried to finesse the search, but the FAA website was not helpful. So I searched on each model number separately, added them all up, and got 3554 Bells of all types in the FAA registration database, which equates to a fleet strength of about 25% more than Robinson. I'm sure I missed one here or there, but close enough.
So now the bet on total fleet hours is a much more interesting one!
I'd happily pay for a beer if someone could trot out the annual hours for each fleet, bet or no bet.