I wonder how they reached that conclusion based on the tiny sample participating; tiny as predicted because most pilots who have the required kit are flying N-reg
The turnout in the end for the trials was actually quite large and enough for the figures to be valid. We will be getting GPS approaches this summer by the looks of it, initially the approaches that were available during the trial and then spreading to other airfields.
I suspect as IO says it will be a long time before the need to haveATC to fly these approaches vanishes but don't discount the validity and the impact they will have. Given the choice of a GPS approach over an ndb I will of course take the GPS anytime, accurate and reliable. Even holding with a gps is easy, OBS the inbound track, wind correct the outbound track using the visual reference of the magenta line and the wind aloft and use the HSI to intercept the inbound. A perfect racetrack every time.