Probably hard to go wrong at that price point. How far is your commute? And how much stuff do you need to carry?
I have two different bicycle-specific backpacks -- a Timbuk 2 Swig and and a Banjo Brothers "Large Commuter".
I got each brand-new on ebay at a price point similar to yours...needed patience, though.
One nice thing about both my packs is that they are designed for "over-the-shoulder" backward glances when cycling...not sure if the frame pack you point to will block your view or not.
Take Care,
Hub [MENTION=12389]hubs[/MENTION]panner