With the exception of Splatbooks, which, thankfully, the OSR is pretty light on, most RPG material beyond the actual core rules of a system fall into two categories: Scenario or Setting.
The differentiation is minor in some cases, and there can be some overlap (especially with the more sandboxie settings) but for the most part, these are the two types of products we buy for our games.
I enjoy settings more myself, even if I'll only use one or two in the long run, as they usually make for a better read, and bits and pieces can always be used elsewhere.
Scenarios are pretty much a one shot deal. You run it and you're done. Most aren't as enjoyable a read (for me) as settings are.
Still, I'm not running anything at the moment. If I was, I'm sure settings would take a backseat to scenarios, as you only need one setting for your campaign once its in motion. I'll need a new scenario every session or two, as I suspect my free time for designing my own will be fairly limited.
It's almost like the question: Paper or Plastic - depends on your current needs.
What are your current needs?
OSR Commentary - Martian Echoes Of S3 Expedition to the Barrier Peaks By Gary Gygax - "The Grand Duchy of Geoff has recently been plagued by a rash of unusually weird and terrible monsters of an unknown sort. This western area, particularly ...
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