Hi Jim,
I've used them a couple of times - first bought some 4 or so years ago - can't really remember why exactly, it was either to increase the amount of times that I could change the dropper flies and still maintain dropper length without having to re-tie leaders or to see if they helped to keep dropper flies more 'proud' of the mainline? or Just 'cos I wanted to have everything that was innovative.
Firstly, the original ones I bought were??? what make were they again? they came in a blue packet with black writing?!? aargh!
anyway - they weren't as smoothly finished as I would have thought and I snapped a few leaders while proof testing the knots so they were binned.
Some time later I saw some or other article featuring the Roman Moser ones, so bought a packet and the finish on them was very smooth - no knot problems. Although the rings are tiny (note that they come in 3 sizes - I think - and I have received various sizes from Sportfish when asking for the smaller ones
) they are quite bulky when you see the ring complete with 3 knots tied to it. Also after a few casts the dropper knot slips round and ends up facing 'downstream' so that the leader is not projected at 90 degrees to the mainline (which may have been the reason for originaly using them)
ALSO, try tying one on - even on a warm day when dexterity, my dexterity, is at normal it's a bit of a monkey! I Keep my rings on a C&F fly threader which allows the first section of line to be easily threaded onto the ring - then - how do you hold it while completing the knot? I then thread the next section of leader line through the ring and hold this 'doubled over' and attempt to complete the first knot.
I've lost a few to the grass at this stage.
I prefer to use the standard water knot for droppers but the rings are still carried with me. I use them for increasing the life of my shop bought tapered leaders and have meant to use them for czech nymphing - with a weaker leader material used on the dropper of the sacrificial nymph.
If you want some pm me your address and I'll post them on.
Iain