Mate they built them on the Gold Coast for many years and I understand they recently moved to Melbourne. They have a good video that shows them tacking the build and using small runs of MIG then a TIG guy comes along and TIG welds most of it. I can tell you on mine the welds are of very good quality.
I know a guy at a Merc dealer who sold them for many years (then stopped because of reasons not relevant) still raves over them and reckons when drilling the Blue Fins of any size the drill was working harder that other brands they drilled including the one they now stock. He believed that the Fin used a very good grade of alloy.
Cheers
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