I have 3-100w Renogy panels through PMW (bogart engineering 2030 with Solar) controller.
I have one 3' section of 12 gauge wire between panels and controller (factory installed wire through wall I can't replace). The other couple feet is 10 gauge.
I plan on adding a 4th panel this summer.
My thought are my camper never meets "lab conditions". I never get full output because panels are flat on roof (2 are tilted only by drop of roof on front of camper), plus by the time the sun is high (still not correct angle) my batters are past the bunk charge state and are doing more Higher voltage finish charge. my controller is also limited to 30a (Charger will safely reduce output if panel current exceeds 31 amp) so I have no fear using 400w worth of panels.
I had the Bogart Engineering Trimeter first, so to me it made sense to just add the solar controller that is controlled by the trimeter. I liked it so much, I bought the same system again when I bought my ArcticFox