I use them frequently, to get harder to reach gear, skills, or other upgrades. I don't care about 100% or any sort of trophy or achievement though. Since I play a lot of older games, I tend to use guides more than most, I'd say. Like, right now, I'm playing Might and Magic 6: Mandate of Heaven, and it's quest and area design are extremely confusing. In addition, certain things can be hard to see, because of how the textures themselves look (a classic is hidden switches on walls, that blend in too well).
Modern games tend to be simpler at their core, you rarely need guides to show you how to finish the game's main story, or even most missions. There are usually obvious markers, handholds tagged with colors, red explosive things, and even distance and/or step counters towards a shouting "point of interest" or quest marker on the map.







