Keep the XT. Your current payments are next to nothing and it won't be the same with an STI. I would use the 3k on the forester and if that's not enough, then you could always swap to a manual transmission later on. You said yourself it didn't take too long to save up that 3k. It'd be more fun and quicker to put the same amount of money into your XT as you would your STI because you would have less payments. I have a feeling that you won't enjoy a stock STI as much as you would enjoy a tailored XT. It's a hobby. There would probably be a part of you that wished your STI wasn't stock...