Hot take: power stretcher vs knee kicker on a 12x15 Berber, no contest
Honestly I did a 12x15 Berber in a rental over in Mesa last week and tried to get away with just my knee kicker like an idiot. It looked fine at first but by day two you could see waves near the doorway, so I pulled it all back and redid the whole room with a power stretcher. Took me 6 extra minutes and the thing lays flat as a board now. Tbh I still don't get why some guys swear by the kicker alone on big rooms, do you actually trust it or is it just faster in the moment?