Magnepan mg1.6 vs mg1.7 bass quality?

Will the 1.7 improve on the 1.6 in terms of bass quality and punch? Maggies are not know for bass punch, so anyone compared both head to head? Will only consider moving to the 1.7 it it can improve on the bass punch from the 1.6. How about toal balance, read somewhere that the 1.7 is brighter and leaner? Would still prefer a warmer, softer presentation.

Currently running a bryston 4bsst2 amp and a cary slp03 preamp