the KAC grips were my favorite for a while, but they all seemed to wiggle a little bit after a while. they can get pretty expensive, but luckily i was able to get a ton of them with various M4/M5 RAS kits.
when the Magpul XTM panels came out, i found that they locked up very tight even when cut in half and offered a lower profile than the KAC. I never had a problem installing or removing them, very easy with two bullet tips. if you follow the instructions, put the bullet tip into the small notch and while keeping upward pressure on the locking tabs, push towards each other, they come right off.
recently, i decided to try the LT handstops on my one AR which included the index clips. they're even lower profile but still durable enough to prevent damage to the rail unlike the soft santoprene rail ladders which will self-destruct pretty quick when using a rough surface for support. on LT rails, they have a tight positive lockup, but they aren't difficult to remove. this is on four different LT rails (two 7.0s, 10.0, 13.2) with various production dates over the past several years. most of the complaints of the LT index clips requiring a dillo or equivalent to install that i've read have been on other manufacturers' rails.
hope this helps.
i have KAC panels on my A4 and MK18 clones, as well as my GSG-5P w/ clone RAS.
i have XTM panels on my wife's SBR (bottom rail only) and my LT stealth.
i have index clips on my one 14.5" M4A1 and i'm currently waiting for the FDE handstops to change over my other 14.5"
And I looked, and behold a pale horse and his name that sat on him was Death, and Hell followed with him.
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