[MOSFET]

I think the crossovers are the main difference in the two. The eclipse
has an 18 db/octave xover whereas the PPI has a 12 db/octave, but the
PPI's xover range goes much higher (up to 4 khz compared to 500 hz for
the eclipse). So if you'd ever want to go active with your setup, the
PPI would be the way to go. The Eclipse also doesn't appear to give as
much power when bridged, so if you ever think you'll bridge it, you may
want the extra 150 watts/bridged pair from the PPI. But if you're just
running them on highs, that's not a concern.

Otherwise I think they're both very solid amps.

KU40 is right. Those are both solid amps and to me it is the features
(x-overs) that differentiate these amps.

As I've said many times on this group, I believe all amps sound basically
the same. However, the quality of construction (MOST IMPORTANT) and the
features of the amp are what differentiates one from the next, IMHO.

MOSFET