Purchasing Decision

I want to upgrade my laptop’s RAM, so I found this. If I buy one stick I will have 1280 mb of RAM and it will cost me $76($66 after rebate). Or I was thinking about buying 2 of the sticks shown above giving me 2 gigs(maxing out my laptop’s capacity), which would cost me $152($132 after rebates). The only problem is that I am saving up for a car, so I want to conserve money. Any suggestions on what to do?