haven't run sundown, but from what i hear they're rock solid.
my vfl 200.1 didnt like low impedence/low voltage. was running it with 2 yellow tops, a 34 series and 31 series, the 31 series was old and worn out, and i believe at the time i had a stock alternator in, while my iraggi was in for service from a popped diode from trying to charge that weak *** battery.
took me a while to figure out my electrical issues were the old battery. i'd say it was dropping to mid 11's, running at .5 ohms, but it took it for weeks until one day it went into protect, i turned it off and back on, and it blew up. granted i abused the shit out of that amp, just sharing my experience.