Hi 2Bigears, I used to work for a gym in Portland Maine. My buddies owned it. Part of my job was to work on work out equipment in other gyms and homes. The Concept 2 rower was the best machine, quality wise than any of the Life Cycles or steppers ect.. anyone could tell. They were the Rolls Royce of rowers. They even published a national or world wide publication for users to keep informed on the machine, like a club. That was in the early 90's. If you could get one used I bet today you could find all the parts.
You can go hard and you can go easy. You can get a light aerobic workout or invert your hands on the grip and do Chuck Norris type exercises that can build you up also, you've seen his devise on TV I bet.
One thing I always thought of inventing for better use of a rower was a seat that prevented you from leaning forward to gain extra pull when your really going at it hard. Your emotion of the workout makes you forget your perfect rowing form and everyone tends to do this, lean forward for extra pull.
I would get off the Concept 2 and it would take me a half hour before I could straiten my back out. I had cheated and used bad form. My seat idea was to have a back on the seat with some sort of straps or a (breast plate) type of pad that would prevent this back strain and make you use all your other muscles that perfect rowing form does. Maybe some one has made this devise today.
The Concept 2 was the next most solidly built thing in the gym next to a solid cast iron dumbell. If you want to row this is the machine to get, Mark Korda...1991. I don't know what they look like today without a google seach, but if they look like the old, buy one!