Caveat emptor: I test fit two different sets of these for Mantis. In the second set, one of four guides fit well. The other three ranged from "you can force it to fit if you hog out the woodrail holes" to "no effing way." For the most part they're too long, but not at one end where you can just trim it. The extra length is spread throughout the guide, making everything slightly (or more than slightly) off. You can see the altered curvature of the new guides on a used playfield where the marks from old guides are clearly visible. It's also easy to spot the discrepancies when you hold an original guide next to a repro.
The L-shaped tabs need their mounting holes enlarged (or moved in a future revision). All the holes are a bit too far back, pushing the guides forward a bit and reducing the width of shots. This is correctable by the end user, not a dealbreaker, but definitely worth mentioning.
I recently returned the second set, so chances are a third (better) set hasn't been made. I'm sure you can "make these fit," especially with new wood rails free of existing holes, but I'd much rather spit-shine my original guides and have the game play as designed.
I don't feel great leaving negative feedback for Kerry who worked hard on these and is a great guy, but I declined to use them in my game, even for free, so I thought others should be made aware of possible issues.
For what it's worth, the two non-guide pieces in this set are perfect: multiball launch flap and shooter lane kickout protector.