Hi, just a bit of info on both bikes. I've got a Pista and a Gunnar (a Roadie though, not a Street Dog) and, while the Pista was fun while it lasted, I regret getting it. The frame and fork are decent for the price, but they are still cheapo Taiwanese steel. The stock parts that came on it wore out quickly. I had to pretty much replace the hubs and the headset a few months after getting it. I found the Sora grade wheels too clunky. Now it's lying in pieces in my kitchen corner, gathering dust.

Gunnar on the other hand is my favorite bike company in the world. Since they are a small company, they treat you like part of the family once you buy a bike from them. Their customer service is unbeatable, and I've driven up to the Waterford factory a few times and been greeted personally by Richard Schwinn and Gunnar. Very cool folks. Amazing quality frames, lightweight steel, good price. The Street Dog costs a bit more but is a much much better bike overall, and it will rock your ass.