Winged it for years and honestly I still mostly do, because aspect only gets you so far once you're a few thousand feet up and the trees change everything. Snow depth maps are great but they're often a week or two old, so a freak warm spell can flip a north slope to slush while a shaded gully stays icy. Check the map, sure, but trust your boots on the trail more than any layer on a screen.

40 minutes down to 9 on a VF-2 sounds like you were touching off every tool in the carousel and now you're not. That's not a gimmick, that's just math. But $600 for the whole machine and you're asking if the repeatability drifts after a few hundred swaps, so you already know the answer is probably yeah, a little. Question is whether a couple tenths matters on the parts you're running, and if it doesn't, why are you even asking us? Buy the holders, check one with an indicator every month, and move on.