These ladder style Picatinny rail covers are a major improvement over the bulkier 1st-gen clamshell types, since they have a more svelte profile and are less likely to pop off unexpectedly or snag something during normal run and gun activities.
Pros: Lightweight and low profile
Cons: These aren't cheap, but appear to be worth it.
This review was written in the old system and had content requirements that are different than reviews written today.