You mean the THC3 LEDs from lsdiodes.com? Those are the brightest red 5mm LEDs I've found so far. They are pretty robust as well. I've used them in place of white 5mm LEDs in a few lights... Dorcy 1xAAA, Inova X1 etc... They are spec'ed at 2.2V or 2.4V @ 100ma and most of these lights provide about 3.6V or 3.8V at somewhere between 20mA and 60mA.
Actually, thought they are just about useless in actual use, the blue THC3 LEDs are freaking bright for 5mm LEDs. They are brighter than cyan or blue Lux 1W LEDs driven close to spec.