HeliComparator
I agree with almost all you've said, but perhaps I can add a little ?
The EASA certification standard for both aircraft is JAR29 change 1. The S92 FAA standard is FAR 29 amendment 47. Looking at the FAA website I cannot see any FAA certification for the EC225, so presumably it doesn't have one yet?
My understanding of the EC225 exemption for "FAR 29.785 Seat, berth, safety belts, and harnesses (Reference CRI D-01)" is that the aircraft is compliant in the 19 seat configuration.
The S92 windows are actually bigger that the standard AS332L/L2 push out windows, so I wouldn't exactly call them small. They are 5 inches higher above the floor than the Super Puma windows. The large EC225 windows are great (and expensive), pity the cabin is still the standard sardine can.
The payload/range/TAS question is an interesting one. Unfortunately the latest EC225 Flight Manual still does not contain any fuel consumption graphs, however the following is believed correct.
The EC225 has a fuel capacity of just over 5000 lbs, assuming 6 under floor tanks + sponson tanks. Without the sponson tanks this drops to just under 4000 lbs. 3000ft ISA -10 at 10,400 kgs AUW, 73% Tq produces a fuel burn of 1280lbs/hr and 135 kts TAS. With reserves + 10% this gives a range of 433nm with sponson tanks, 333nm without.
The S92 has a fuel capacity of just over 5150 lbs. 3000ft ISA -10 at 25,000lbs AUW, 66% Tq produces a fuel burn of 1320lbs/hr and 135 kts TAS. Taking reserves + 10% gives a range of 430 nm.
Nothing in it.......
However the S92 does give about 1000 lbs less available payload for the same spec of aircraft. Sikorsky are planning (??) to increase the MAUW to 28,000 lbs, so I guess some time in the future this will swing in favour of Sikorsky by about the same margin.
As you said, the only real difference at the moment is price, with Sikorsky being more cost effective to purchase and operate by a margin of about 20 - 30%. A strengthening dollar will change that - anyone have a crystal ball??
One minor point, it's a shame that ECF have not developed a crashworthy "enhanced" crew seat. Their only offering is a basic seat without all of the usual adjustments, supports and armrests.