I grew up with a lot of these books. The first one I remember was one of the Choose-Your-Own Adventure books called House of Danger, in which you play a detective looking into a disappearance at some old civil war building. It had bizarre ways to die like being turned into Grade A frozen meat for aliens, or having your mind put into your future self and dying of old age. It kinda gave me nightmares back then.
I also read Be An Interplanetary Spy after a cousin introduced me to his copy of Robot World. My older brother bought a copy of the first Grail Quest, and we started picking those up every time they showed up on the book list for those monthly book purchasing things they used to do in elementary school.
There were a good number of copycat books that we got into. I started tracking them down using eBay and Alibris some years back so that I could share them with my own children. I've got about three of the Interplanetary Spy books, several of the Choose Your Own Adventures, a few GrailQuests and a dozen or so of the copycat books that I had remembered (can can't for the life of me recall the names of at this moment at the office). I loved these books, and hopefully my daughters will lvoe them too (once they're old enough to read).