I have to admit I was a skeptical that the Hypershell would make a significant difference to my walking abilities. Have since done 3 walks and 10 km with it and have to say it is an incredible piece of technology. I'm 66 with early OA in both my knees. Struggled with distance walking and was reluctant to walk more than 500 m each time with 1km about my maximum. With the Hypershell I have easily done a 2 km, 3 km and 5 km walk so far. That is with stops of course but I can now double my distance between stops.
Pros:
1. Definitely helps up steep gradients
2. Certainly contributes to leg strength and support
3. Makes you want to do a walk when you would otherwise hesitate
Cons
1. Doesn't give as much support going downhill as much as I hoped it would
2. On the Hyper mode the motor can heat up significantly, enough to make you feel uncomfortable
3. When I detach the battery for a couple of days, it seems not to have a "memory" to last those days and I have to restart the whole process of initiating the Hypershell again right from tye setup process.

Other than the above, it's a pretty incredible product. A bit like an e-bike for your legs.

Great product! Only reason I gave it 4 stars instead of 5 because I wanted to suggest a possible improvement. Not sure if possible, but can future iterations help you go up a couple of steps? It helps me lift the leg but doesn’t help pushing up

I bought this not as a mountain hiking assist. I bought it to see if it would help my waking. I've had a few back issues and have 50% paralysis on my left leg with numbness, my right side doesn't have any paralysis but is numb.
Anyway this Hypershell pro X has been amazing! I've had it for almost 3 weeks and have walked 12 miles to date, I walk at least a half mile per day, my longest single outing was 1-1/2 miles, I do have to use trekking poles to help with my balance,
It took some time to get the Hypershell set up for me which I still have more features to tweak but I'm getting stronger every day. I think the damn thing is helping.

Surprising. Mostly for going up stairs or halls, i need to try

Increased my limits from an uninterrupted .25 mile to .6 mile/ hour limit from .6 mile to +1 mile. It helps me get tired slower; Better than nothing