I'd agree - I've never run a single that was as smooth as a twin. I miss the small hp twins of my youth.
I think a lot depends on your personal factors. Such as....
1) Do you expect it to "get you home in a hurry"? Or do you want it so you can "get to the side of the road" and wait for better conditions, make a repair, or putt on home later?
2) Do you want to be able to control it from a tiller in the cockpit? Install a second helm in the cockpit? Control it from the main helm?
3) Will you be fishing a lot with it? How "fine grained" do you want the control to be from the helm? (Just steerage, or speed and shifting too.)
4) Do you want to be able to easily lift it on and off the transom at times? How much weight can you easily lift? How high a priority is light weight vs. heavy weight? Related to this possibly is what side of the transom do you plan to mount it on (considerations of balance, swim platform use, tiller clearance, etc.)
5) Do you want it to have an optional separate fuel source (in case of contaminated fuel?
6) Will you also be using it on a dinghy or is it purely for the transom of the big boat?
7) Can you tilt a large/heavy motor safely while leaning over the transom? If not, you may want to consider a "lever arm" or power tilt/trim.
I'm sure I could think of more questions, but that gives you the idea.
For me the answers were as follows:
1) Get me to "the side of the road" where I can do what I need to do. No need to "get home in a hurry."
2) I wanted to be able to control from tiller in the cockpit for sure. Other means optional.
3) Not fishing much. No need for super fine grained control, as I'd be using the main most/all of the time.
4) I did want to be able to lift it on and off the transom easily by myself. For me this meant around 50# or less. Mine is mounted on the starboard side (swim platform is to port, which I use a lot, and which I like on that side as no cables/hoses/etc. there). My boat tended to be starboard-heavy with the larger motor, so fixing that was a goal (lighter motor did that).
5) I wanted a separate fuel source, but also didn't want to always have to have a separate tank. So the motor I got has an integral tank, plus the ability to be hooked up to an external tank (have it then set up to run off main tank/filter).
6) Purely for transom of "big" boat.
7) Leaning over the transom to tilt/lower larger motor was an issue. I could have used some sort of lever (they make them) to assist; however with the lighter engine it's not a problem.
I don't know if any of that helps, but maybe it might.
Sunbeam