They could be worth investigating.
I did the walk last night. I arrived at the rv later than planned so only had time to walk to Black Moss reservoir and back before the 15 mile round trip to White House. The guy I went with is an ex Fell runner too but 14 years younger than myself. We set a really good pace in the dark and were there and back inside of 5 hours carrying the full Spine kit.
Here's the dilemma with my new Hedghogs, Got to the White House with no ill effects. We had a brief stop of around 10 minutes. As soon as we set off on our way back, my left foot PF flared up again with my heel quite sore. It progressively became worse with the shoe feeling very hard underfoot (Sorbothane Double Strike insoles in place). After a couple of miles my outer foot became painful, as had happened on numerous occasions before. Usually follows the heel pain. Also as usual this outer foot pain became more of a problem than the heel pain. I could only ignore the discomfort and carry on at the good pace we were setting. Back at the car, it was really bad as it was this morning, but has now eased off some.
My right foot however was comfy the whole time, so I can only put my problems with the shoes down to my continuing PF.
The other guy was wearing his new Hoka mid boots and says he is really impressed by them and he will using them during his Spine Challenger.