I got a Renegade Expat about 18 months ago and LOVE it. I do ride primarily on the road, but the road conditions can vary wildly from smooth pavement, to a potholed mess, to unpaved.
I have found that overally I actually ride slightly faster than on my old road bike (Giant OCR carbon). I have seen studies that slightly wider tires actually have lower rolling resistance. However I think primarily it is the increased overall comfort that gives me the boost. The ride is far less jarring and more comfortable overall. I am not however a racer so YMMV.
I will say that I had to take it in last year for about 2 weeks as one of the brifters broke (warranty replacement) and on my first ride out on the Giant, I hit a small bad spot on the road and blew both of my tiny tires. The renegade definitely would have been faster that day...