I'm just using Eurocopters own data:-
Puma helicopter, super puma - Eurocopter helicopters - Eurocopter, an EADS company
which says:-
The EC225 has evolved from the vast experience accumulated by some 100 Super Puma operators; some 900 helicopters have been ordered in 52 countries. The in-service Super Puma fleet has logged more than 4,4-million hours and the fleet leader has flown 39,300 hours.
One assumes therefore that they are now being clever with the mix and match of types.