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.

There are 4 main rowing machine types that are classed according to its utilized resistance mechanism. Having an exercise workout needs to have resistance against the movement in order to provide to the muscles and the cardiovascular system a good change. This can be provided by the rowing machine whenever you pull its handle and then slide back to the seat. Having low resistance works on the cardiovascular system can make you row fast easily. Having high resistance means that it provides you with the anaerobic session, working with the muscles harder, also having a slow stroke rate because of the harder pull.
From a fitness perspective, the WaterRower Classic works 84 percent of your muscle mass, helping tone and strengthen your muscles while burning far more calories than most other aerobic machines. The exercise is also low impact, as it removes all the body weight from the ankles, knees, and hips, but still moves the limbs and joints through a full range of motion--from completely extended to completely contracted.
The advantages with air rowers is that there is smooth action; there is only small wear and tear to its mechanism; its automatic feature adjusts according to your rate of strokes; and there is a wide range of the resistance readily available in replicating the feel of rowing through the waters. The only disadvantage of this machine is that it tends to be noise indoors.
Flywheel sits in enclosed water tank to provide smooth, quiet, self-regulated resistanceSeries 4 performance monitor tracks workou...t intensity, stroke rate, heart rate, and moreHandcrafted rowing machine with "water flywheel" that replicates actual rowing feelStores upright; measures 83 x 22 x 21 inches (L x W x H) and weighs 108 poundsNo impact and Non-Load Bearing, perfect for users with Joint concerns read more
In sweep or sweep-oar rowing, each rower has one oar, held with both hands. This is generally done in pairs, fours, and eights. In some regions of the world, each rower in a sweep boat is referred to either as port or starboard, depending on which side of the boat the rower's oar extends to. In other regions, the port side is referred to as stroke side, and the starboard side as bow side; this applies even if the stroke oarsman is rowing on bow side and/or the bow oarsman on stroke side.