I really can't make any kind of assessment because we've had exactly one frozen precip event in Tarrant County since we set them up. I'm a little bit skeptical of their performance because acoustically speaking, wind driven graupel would behave quite differently than pure dendrites falling softly. But anyway, I'd have to look more into it.
Our own sample size aside, the Parsivel disdrometer should be good at that because it images the hydrometeor shapes and calculates their fall speeds, which, when combined with air resistance equations should give an estimate of density. We submitted a proposal to NOAA to install two of those here in the northeast, one in a coastal location, and another at an elevated inland location to look into that exact problem, but the decision is still pending.