All these altiports are surrounded by copious amounts of wreckage
Mostly just Courchevel, which attracts people who should know better because they keep the runway clear of snow in the winter. There are far fewer accidents at the other altiports, although all of them except Megève are more difficult than Courchevel.
VMC-on-top - on a nice day with a GPS, it is a piece of cake to find it as long as you use a bit of common sense. Without a GPS it has a tendency to move from one valley to the next.... On overcast days, it sometimes seems to disappear altogether.
Re Chambéry - it's 48 hrs PPR by NOTAM until April 18th, with restricted access, special VFR routes through their (class E) airspace, very limited parking availability, and inevitably on a Saturday lots of commercial traffic complaining about having to hold for so long. Fine on other days, but best avoided on Saturdays.
LH2 - where do you fly from?