if you're just going to be running stage 2, go with the wrx. it has less miles and with the $2k you can get an sti turbo and intercooler and have money left over. I know in 06 the wrx and sti had the same injectors and fuel pump so i'm assuming those wont need to be upgraded. you'll essentially have the power of the sti for about a grand less with 40k less miles