Looking for an incredibly dynamic preamplifier

I'm looking for a dynamic preamp that provides plenty of attack, great bottom end, and an iron-fisted grip on the system. The best I've heard so far (and by a long shot) is the Wyetech Labs Opal.
I would assume that other units with robust outboard power supplies are good candidates? Maybe a battery-powered unit like the new DartZeel pre would qualify?
Thanks.