With the numbers presently found on gear, crit is usually a higher boost to your statistical dps. Yes, it is more unreliable than determination, but over the course of a regular encounter crit will almost always result in higher numbers. The RNG madness of crit is really just an issue with low hp / duration encounters, but in those cases it shouldn't make much difference either.

Another thing to keep in mind is that the difference between secondary stats is really, really small - if you compare a full det build vs a full crit build of same ilevel the differences in damage are likely gonna be smaller than the standard deviation from spells or testing errors.