Aye, I have the measure of that now I think.
I got pretty far into Skag Canyon (?) looking for stuff after killing 9 Toes but had to back out after running into Adult Skags on a regular basis.
If I'd kept going they'd have respawned behind me and I'd have never have gotten out alive.
(Still, got two Level 13 weapons......that I can't use yet.

)