Meh, I say there is no point in changing springs unless you go up or down. I highly doubt you will be using the extra stiffness at this point. Once you pull the suspension apart, you need to pay for an alignment. Seems like a lot of work (for someone else) and money for you just to say you have "WRX" springs.
If you're pulling it apart install a lift kit with those springs, or grab some used drop springs. Save the trouble and your money.