Sorry let me re-phrase, landings at the end of you jump range on hard terrain can be rough/tough. You have much more energy to dissipate and hardly any padding to help. So you certainly have to be dead on with technique. It's quiet different from ...
The landing with them is pretty rough. I think they are best to practice things you've done enough to be confident with, watch doing precisions and things at the end of your jump range.I can see stubbed and broken toes happening easily other wise....
I've been doing things like this since i was a kid. Started gymnastics in 3rd grade. Diving in 10th. Yell leading in 12th. Been doing parkour under the name since 2001 - 3.