Andrew, with this topic in mind I've kept my eye on the IVSI on the landings/touchdowns of a few captains. I don't fly the 747, but the 737, but in theory the comfort for the pax should be thesame
. One was on a superday (straight down the runway at 6 knots), which was a natural greaser. The touchdown rate was just under 100'/m (About 75 I think).
Watching it on the more normal landings it was between 200-300'/m.
Just some figures so you can compare them to your touchdown rate, though from a different type.