2 Midnight classic 250-cp controllers started it all. I grabbed then off market place and designed the system from there. it's now been over a year and the system has never blinked no matter how hard I run it. I have 4 sunpower 250 panels in series on each controller. That's 200+vdc running into each one. the front 1000w is split by the AC, and the rear 1000w goes right over the rear AC.