that sounds like a good idea, those fluorescent transponders, but wouldn't it be simple to paint them yourself? (Would also eliminate extra production-costs for Terry ... and by doing so, eliminating extra costs for buyers).
Since Terry's transponders are water-tight, I guess it would not be to difficult to place a little piece of tape over the led on all PT's, and then paint the whole lot of the transponders with a gentle paint-coat.
That would we sufficient to recognise the Club-transponders from PT.
And if the gentle paint-coat wears off, it would only take a 10-minute job to give them a new coat.
Only my 2 cts