i think the general consensus is that dc resistance is a very rough estimate of the output, though as it changes dependent on thickness of the wire etc., it's far from ideal.
Dimarzio also use mV outputs, which is probably a little more accurate, but this also depends on how hard you hit the strings etc. so again isn't really ideal. And since no-one else (that I know of) posts outputs in mV, it's only really of use when comparing a dimarzio to a dimarzio.
It's no help at all when dealing with EMG's (resistance), because they use a pre-amp (i think) to bump up the output.
best bet is to try them, or at least ask someone like tim who has, lol.