Seems standard, and seems ok -- I've never used Durabrand, so I'm not sure. But I'd imagine it's fine. Just don't let them, or Best Buy, install it. Circuit City's ok, if you have one around -- I learned that Wal-Mart and K-mart (including Best Buy), the ones that have installation available, use hot glue, instead of using molds/clips to install. This will go to crap after three years on your wires -- I had issues, and so did many friends of mine. If you do use them, just tell them no hot glue.
But you can probably do it yourself with the 20 dollar 'car kit' if you ask them.
sorry couldn't be of much help