I just went through the same decision as the OP and ended up with the Kowa paired with a 500AH. I just don't see myself using the modular system of the Swaro and I hate chromatic aberration which the Kowa handles beautifully. The fact that I could buy the scope plus the 1.6x extender, plus case and tripod head and still come out less than the Swaro didn't hurt either! The 883/500AH is an almost perfect combo. The 500AH is a big head in volume, but doesn't way a ton and the pre-set drag is just about perfect. It was very easy to balance the scope using the spring balance and supplied manfrotto plate. On a recent day on the water, looking west into the sun (birds were backlit) there was zero and I mean zero purple or green fringing--just incredible!
My only complaints (and they're minor) is that it is not compatible with Arca-Swiss plates...I have lots of Kirk plates and none of them work. Second, the lack of rubbe armor is noticeable--the scope feels delicate and would certainly take on damage from even a small drop onto a hard surface. A Kowa canvas or neoprene case is a must (I have the canvas which is functional, albeit ugly).
Can convert quick release plate of standard 39mm Arca fit to GITZO ball head. Suitable for converting quick release plate of standard 39mm Arca-swiss interface to ball head of 50mm GITZO interface. iShoot Quick Release Plate Adapter IS-5160JX.
I see that they now make full-length adapters which might be nice for some applications but in my experience not necessary as the actual clamping area of Manfrotto heads is usually short. Still, I think I will get one or two of these for future use.
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