Left sided here. Started out close in size initially, but the right side is dismal now... Despite much effort in maintaining supply with it. I would always start feedings on the right and then switch to the left for the majority of the feed, just to keep the stimulation happening to the right. Pumping is indicative for me. I've only ever got max 50mls from right and 150+ from left. This indication is from pumping the same time every night for the last 3 months. These days I'm only getting about 20mls from it. So you can just imagine my lopsided-ness is next level!