The reason I'm writing now, two years after purchase, is, I broke one of the wheels. I proceeded to order the wrong replacement, so I emailed them pictures to ask for the right parts. They wrote back asking for the serial number to get the right unit AND to see if it was under warranty. (Hadn't even occurred to me.) Turns out it was, they're sending me the wheels, they're refunding me for the wrong part, AND included a link for the Puri-Tabs which I didn't know they provide for the life of the ROWER! They're also replacing all eight wheels even though there's only one broken one.
The main advantages of the water rower are that it has quiet operation; there is only little maintenance to do, the water only needs to be changed occasionally; many users love the whooshing sound of water in the tank; and its consistently smooth resistance at every stroke. Two disadvantages of this machine are it costs a lot than the air rower; and it tends to be larger in size compared to the other rowing machines.
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.
First of all, if you're considering rowing, just do it. It is by far the most enjoyable and beneficial exercise I have ever tried. I've made huge strides with both cardio and muscle fitness with the WaterRower, and it's so enjoyable I look forward to exercising each day. Yes, it is more expensive than most other rowing machines, but when you compare it to a lot of other types of exercise equipment, it's actually pretty reasonable. When you also compare the exercise benefit you get, it's a bargain.
The rowing machine itself is unlike any other on the market with its patented water filled flywheel. It is hard to exactly copy the action of a scull on the water, but the mechanics of the flywheel spinning in water comes in a close second on dry land. The fact that the water is 800 times denser than air means that there is no need for any extra resistance or dampening that you will find in normal air rowers. The faster you pull, the more resistance is generated giving it infinite variability. However, if you want to be able to practice rowing with a faster stroke, you will have to reduce the amount of water in the tank unlike an air rower where you just have to adjust the baffle.
Other details include dual rails with four corner wheels that increase seat stability and reduce the amount of sweat buildup; a frame that flips upright for handy storage; and a weight capacity of up to 1,000 pounds. The WaterRower Natural measures 84 by 21 by 22 inches (W x H x D), weighs 117 pounds (with water), and carries a one-year warranty on the frame and components (WaterRower will upgrade the warranty to five years on the frame and three years on the components with the completion of a registration form).