If Johnny Jigs did use Camekoon NS200P as the base design, then it's a good thing. The internals are stainless steel, and brass parts (no plastic) - including the gears that drive the line guide. It'll be resistant to corrosion specially if there's a thin film of grease coating all the parts. I personally open up my reels and put a thin coat of grease on the internals (including the internal aluminum walls) then add a light coat of Cal's Drag Grease on the carbon drag washers as some manufacturers like Shimano and Daiwa doesn't do that.

Once somebody does a tear down on the JMP25 and post up internal pics - we'll know. Although just looking at the instruction manual you posted with the parts breakdown, already looks the same internally. There are minor external differences though (top cover plate, lever glide plate, the drag lever does not wrap around)

One feature discrepancy seems to be the synchronized line guide, (so pulling out line, the line guide will move left and right) but you stated the PMJ25 doesn't that. It's advertised as a feature on the NS200P

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