One "gotcha" to beware of with user waypoints: if you do a "clear all" reset, they go!
(Especially if it's early in the morning and you're just starting the coffee while looking up the valley with building nerves. Not that I've ever done that. Oh no.)
I'll probably be waypointing my campsites for LEJOG, though. It's just easiest. Plus, if you use a consistent symbol for them only, at least you can delete all of one symbol (eg, delete all - red flags - for the day's scratch waypoints).