I don’t want to rain on Nick L’s parade but EGPWS in a lot of places helicopters operate aren’t worth the money.
We fitted at an oil company expense EGPWS.
The system worked as advertised, predictive path and all the bells and whistles that bitching betty could muster.
There was one significant factor that the manufacturers overlooked. The terrain database (Honeywell) in this case was incomplete, so much so that for remote area ops, Betty was Bitch’n all the time, and we flew with “Terrain Inhibit” engaged most of the time because the system did not believe that there was a landing area in that location. Thus negating the E part of the system.
In PNG it was even more ridiculous, earning the name “Great Papuan Railways” ie: constant calls of Train Train.
If you are remote, serious off strip and places without ground based aids, in other words where you find Helicopters and their support aircraft it is not worth it IMHO.
Newer systems suited to helicopter ops will be forthcoming that are more prepared to deal with remote locations.
Hoggie