Yes, apparently the older non-Kevlar versions were pretty weak.
However, even with the Kevlar belt, it won't measure up to the Armadillos. I went from 'dillos to Marathons (not the Marathon Supreme) and the puncture incidence went way up.
not trying to scare you or anything.... just letting you know. the 'dillos are pretty special: much better at flat prevention than any regular keval-belted tire out there, that i have used anyway.