Waterrowers are the exercise rowing machines that use paddles in an enclosed bubble of water (as opposed to the Concept II types with springs and pulleys for tension).
I’ve heard they’re good, more realistic than Concepts, but I’ve never tried one. The niftiest one I have used is a Rowperfect (here), with the flywheel moving as well as the seat. They’re great. Concept 2s are still pretty good though. Have you tried out the water one?
My gym got a waterrower when they refurbished the entire place a few months ago.
I love it!
It’s a heck of a lot easier to use than the old rower they had. It also gives you one hell of a workout, considering that your body weight plus the water mechanism provides the resistance.
Unfortunately, I’m in a minority as far as the rest of the gym members are concerned. I’ve never seen anyone else use it