I use a Markins M10 with screw clamp, and an M20 with lever clamp.
A screw clamp has fewer issues. It only takes a couple seconds more to work a screw clamp. As mentioned above, it is very easy to mis-thread a screw clamp; I had a few near tragedies with a 300 2.8 until I learned to do the shake after clamping. It would be a lot harder to mis-thread the plate on a lever clamp; maybe impossible but I don't want to say anything is impossible
If you ever consider a Wimberly Sidekick gimbal, read Wimberly's advice on their site regarding RRS lever clamps. You may need a $43 adapter, which was the route I went.
(I also prefer Wimberly lens plates because they are longer and generally more flexible in terms of positioning, and they are more generic so can be used with future lenses. Wimberly thought through the issues of precise balancing more thoroughly than RRS because they make gimbals. I just converted two collared lenses to Wimberly plates. I have some RRS plates for sale

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I have a Kirk 300/4 replacement collar that DOES work with my lever clamp and I have seen other reports here where Kirk plates were successfully used with the RRS lever clamp. The compatibility issue is probably more theoretical than real but if you have a lever clamp, you always have that uncertainty hanging over you if you use other plates. Also, with time and use, either the plate and/or the clamp could wear, I guess, and a non-problem today
could , in theory, become a problem over time. Plus, you never know what plates you may want to buy in the future and who makes them, etc., etc.
Some people are concerned about the lever being accidentally opened, for example, walking through the woods and getting a vine or branch caught on it. I've never seen a report of it actually happening. Some lever users are concerned that a screw clamp could spontaneously loosen; I have never had that happen myself, and I used the M10 screw clamp exclusively for over two years. My own attitude is that lightening could strike either clamp design.
If you are still on the fence after all this, consider how often you will actually work the clamp. If your shooting style is to set up and leave things that way most of the day, the choice is somewhat irrelevent in terms of convenience. If you have an L bracket and you are constantly flipping from landscape to portrait mode, you will more appreciate the convenience of a lever clamp. A lot of my work is with collared lenses so I don't get the full benefit of a lever clamp.
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Regards,
Neil