Comfort Bike for commuting? I currently have a Trek 3500 Mountain bike which I use for commuting 34km total each day. I did put on thinner tires. My average speed is about 20 - 22 km/hr
I'm tired of the leaning forward all the time and was considering getting a "comfort bike" where the handlebars are higher than the seat.  This would provide a much more enjoyable view/ride. I'm thinking something like this:
http://www.primeauvelo.com/en/cypress-dx-42604-0014040.html

IMHO I am guessing (please correct if I'm wrong) that once you go non-road bike, the differences of hybrids are marginal.  I believe most (all?) hybrids have more or less the same top speed, and my question is - would a comfort bike be more or less the same as a hybrid, but a hell of a lot more comfy.
I commute on 28 km/day at 22-25 km/h average. I normally use a city bike, where I am not exactly leaning forward but neither sitting at 90 degrees.


However, I had to use for an entire week a different model, where I was more "seated":



though at the beginning I was feeling more relaxed, on the long run it was not that comfortable: keeping a decent pace was a struggle (drag and head wind, feet slipping on pedals), and also the steering was far less precise than I wanted, resulting in slower rides.

Maybe see if you can borrow such a (or similar) bike and use it for a week or so, before switching to it.