I started "gaming" back around 1980. Stayed active until 1997 but remained as a collector and reader and wanna be gamer. It wasn't until 2007 or so that I actively returned to gaming. Even before I was "returned to active duty", I had found Castles & Crusades and my door to what would become the OSR had opened for me.
I am OSR through and through, and I'll be the first to admit that we have a huge variation of rulesets in our niche of the RPG hobby. When I saw that the Old School Renaissance Handbook had been released, I was psyched. Not because I thought I needed it, but figured it might remind me to take some second looks at rulesets I may have quickly passed over previously. Sometimes having a huge selection to choose from leads you to inadvertently limit your choices.
I'm happy to have been reminded about games like Dungeon Raiders and Dungeon Squad (this was not a reminder - somehow I had never previously heard of Dungeon Squad). It makes me want to take a second look at Microlite74. It does so with a nicely bookmarked PDF and a convenient listing of the games looked at, along with hand links to find them online (and their pricing). Very handy stuff.
It's a quick read, especially if you are like me and find stated out characters to be a bit boring after the first few.
Still, the information is good, especially if you want to show an non-OSR friend the different styles of rules available. It's like a "cheat book" of OSR cataloging info.