Interesting - I didn't know your red tops croaked. Must be a 24V thing - I got mine at the same time from the same batch of blems and they are still working great in my 12V 70. My BIL and another buddy also got 1 each at the same time and both of them are still working fine as well, also in 12V situations...
Ya, they did not like being stacked in series for 24V at all...Even the yellow tops do not like it much, however having the converter go to load balance when running seems to be looking after them.
I think the damage was done. Lasted for a while in parallel in Poo, then simply gave up one day.
gb