TNNs came along.
I swapped my LGMs for a set of koxx red pads (pretty similar to browns) and they worked about as well as the LGMs, although not as good in the wet.
At the end of the day all the top pads are pretty similar, just have quirks that make them suited to certain people / set ups / riding styles.
Having said that, I loved the koxx browns (ran one brown and one tarty adam black pad for aggges, awesome) and the reds too, but bought a set of yellows and they were the worst pads I've ever used (including Monty Orange pads). No matter what I did with them, they were shit.