So, just how much is your $1500 road bike worth to you? That's the question you have to ask yourself.
Do you leave it on the street during the day? you might want a decent lock.
Or just for a 20 minute espresso and popover? Maybe something slightly smaller and more convenient.
Or perhaps on the street overnight? I might suggest the biggest, heaviest lock you can find and don't forget to lock your rabid pit bull to it.