OK, so because the fly has a moulded ball/weight on the hook it is not acceptable to be classified as a fly by some!!!???
My 2 cents is that using a "jig" fly is is still fly fishing even if some use a similarly designed hook & weight for conventional fishing. The weight you use is dependent on the weight fly rod you are using, heavier the fly heavier the rod. The weight 1/124 oz I would comfortably use with my 2 weight fly rod and possibly 1/80 oz.