I love danner and the regular mags, but the hy-drives are crap.
the impellors are wrapped in cheap stainless with the copper windings in the impellor. within a few months, the steel wears thin and exposes the copper. the 2100's even have the windings exposed directly to the water at each end of the impellor.
I manage a salt shop and we went to all hydrives for the systems. within 4 months, all the pumps (and the replacements) were dead and the main coral system had readable amounts of copper in it.
we switched over to the quiet one line of pumps.