Of the four types of rowing machines or ergometers, water rowers are best at reproducing the sensation of on-water rowing. Their stroke cycles hold true to the dynamics of real paddling, and each stroke is punctuated with a splash! Water rowers have sliding seats to allow full-body cardiovascular workouts. (With cheaper rowing machines, in contrast, the seats don’t move.) These fitness machines tend to feature high quality parts and can last a lifetime.
However, I own an air rower and have zero worries about maxing out it’s ability. I can completely exhaust myself on any type of workout. Air and water rowers are the chosen resistance type by Olympic athletes and any athlete looking to train their full-body cardio. I don’t think they would choose this resistance type if they felt they could max it out.