That bike looks like a terrific spec for the price.

There's a feeling I get from some bikes but not others, that every bit of effort put into the pedal is being turned into forward motion. It's the frame and wheel design, and the geometry. I've gotten this from aluminum and steel, fat tires and thin. But every bike that has given me this has been made of road-bike tubing and has had good wheels. I get it on my Paramount (steel sport touring bike from 1976) and I got it on my Cannondale R2000 (aluminum racing bike from Y2K) and from an Expert TG (a steel racing bike from the early 90's) but not from my current commuter, a Cannondale XR800 which is a cross bike and is a combination of road triangle and MTB rear end, and not from my Super Sport which was h.e.a.v.y. There's a category of bike called a "sport touring" bike that is not so popular now. It has medium reach caliper brakes to clear medium tires plus fenders, and may have a more relaxed posture and lower gearing, but it's made of nice road bike tubing with nice road bike wheels. The major manufacturers are mostly pushing "gravel bikes" or "cross commuters" for this marketing niche but they are not quite what I mean. Examples you can buy today... http://www.bikeforums.net/commuting/...nar-sport.html

Rolling resistance is nearly all in the tires. Knobby tires, even good ones, are just not going to be very great on the road, and construction matters a lot too. Skinny vs fat tires is a popular topic and you can read up on it, but I think if you are sticking in the 28 to 32 mm tire range, it's sort of secondary to quality.