I am hinging on this

Good news is, you can always buy another wrench! (The set that I got several years ago came with a little drawstring bag, and I keep both the wrench and extra pin backs in that bag - haven't lost it yet)

Locking pin backs are AWESOME. I haven't had any issues with them scratching things since they're super smooth, but I could see it possibly happening if they were crushed/scraped really hard against something.
(For reference, this style is what I'm referring to) www.pinmart.com/locking-pin-...