I can see where those rings could be useful and save $; however for aesthetic and elitist reasons I don't think I could use one

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As far as mono to fluoro you have to be careful what knots you use. No dbl surgeons! Triple works fine as long as there is not a lrg dif in diameter.
I also like the uni knot for tippet to fly. You can leave (or open up) a loop at the end of the tippet to give a nymph better action or to help eliminate micro drag on techi dry fly water (great for trico spinners).
Tight Lines
MarcP