I picked up a K1 and an L bracket several months ago. I thought that I had researched pretty much all the possibilities - RRS and Kirk along with a generic that didn't appeal to me at all. This is the first I had heard about the one from Markins.
In the past, I used the Kirk for my K20 and K5 - which worked perfectly, very snug. This time, I went with the RRS one because it hugged the side of the body better than the Kirk (based on the product photos). So far so good, it works, and fits very close to the body and I'm very happy with its performance.
I'm now sitting here comparing the RRS (in hand) with the Markins (via photos on ebay). The Markins bracket in the image is difficult to tell if it's any more snug than the RRS. I doubt that it's a worse fit. I think the only way to tell is to actually have both items and fit them on a camera body.
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Quote: Did you have any issues mounting the combo to your tripod? I've never used an L bracket before, I've seen some vague talk on different forums about compatibility issues with different combos
I've had no problems at all. I have used the L Bracket with my ballhead (Acratech GP), geared head (Manfrotto 410) and my pano head (Nodal Ninja 5). I'v have settled on a common Acra-Swiss clamp and plate system. I have had no interchangeable problems across Kirk, RRS, Acratech, Sumwayphoto, Fanotec, etc. It's all been plug and play.
I have even attached a Sumwayphoto clamp on to a Manfrotto plate (for the geared head 410), essentially converting a 410 Manfrotto head into being Arac-Swiss compatible.