Philadelphia has the distinction of being the birthplace of many things, among them amazing cheesesteaks, the Manayunk Wall, and Rocky Balboa. However, there is another item that can now be added to the list, the Symbiot Sportback
This backpack for the active lifestyle is one of the most comfortable backpacks I've ever worn. It fits snugly around my torso (eliminating the usual shifting you get from other packs worn over the shoulders) and fits perfectly against my back in the tuck position (less of an effect from the wind). Plus, the padding you get for your back is very thick and hardly keeps you from noticing it. You don't have to worry about not having enough pockets with the Sportback either, there are plenty provided for you.
Although space is limited in these (don't plan on carrying a large laptop in here), there is still more than enough room for the things you'd take for a spin. Plus, with bladder compartment as part of the Sportback, there is practically nothing you cannot do with this bag.
As compared to other bags out on the market right now, you should expect to see sales of this bag grow once the word spreads.
And as a bit of trivia, the latitude/longitude coordinates on the Sportback tag are as follows:
Plot those and you'll learn a little about the company.