Water rowers are just a recent invention followed by the air rower, which utilizes paddles and water in order to create the resistance. While there are a lot of people who prefer the air rower compared to this one, there are also people who prefer the water rower because it has a smoother, quieter feel of the action, especially when emulating the movement of water rowing. Like the air rower, this machine is able to burn calories and work up your muscles through offering resistance to your movement while sitting on the sliding seat. The more resistance there is, the more it makes it harder to work on the machine and your workout becomes more challenging.
If the machine is to be housed on a wooden floor you will need a mat beneath to reduce vibration and also noise. If space is tight, the hydraulic options are usually the smallest. It's also worth checking your floor can take the weight if you're going for one of the bigger, heavier models. For most, this shouldn't be a problem, if you have any doubts get a surveyor to check as it could be a very expensive mistake!
If you are anything like me, you read the negative reviews to see what some of the complaints could potentially be...I have found none that match with my machine or experience so far. The boxes it came in were a little bunged-up but everything on the inside was perfect. Only took about 15-20 minutes to build (first time building a row machine) and another 5-10 to fill with water. We used it for a little while before we added the danish oil.