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.
Con's: Super bummed that for $1160 they couldn't include an internal ANT+ transponder and Heart Rate strap(sub $100 package). The foot straps are crap! Within the first 1000m of moderate rowing they loosen to the point of being able to pull foot out on Recovery of stroke(Yes, even with ball of foot down). I really wish the WaterCoach F.I.T. software for the S4 Monitor was macOS compatible. It'd be nice to able to customer program workouts on my MacBook Pro or iMac.
If you’re interested in using a rowing machine for focused training — whether for outdoor rowing, an indoor competition, or as part of a larger fitness program — you’ll want air resistance. If you’re drawn to rowers for the enjoyability (alongside the full-body, cardio-plus-strength training efficacy) of a rowing workout, consider a machine with water resistance.
The Water Rower comes partly preassembled in two large boxes. The assembly instructions are reasonably good, and as long as you take your time and follow them carefully (read all the text) it takes about 45 minutes from opening the first box to trying it out. I bought bottles of distilled water to fill it, which made it easy to fill using the included funnel & hose.
From a fitness perspective, the WaterRower Natural 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.