I see you got a good offer recently on a 2007 spec.B, $500 below invoice (see http://www.legacygt.com/forums/showthread.php?t=58164). Sometimes if you wait until very late in the model year, like it is now, you can get some good deals. But you have to settle for what's left and might end up paying for something you don't want, like a spoiler.
You'd pay less for that 2007 spec.B under the VIP Partners program. Plus you don't have to wait until the end of the model year to buy your new Subaru. You'd have the option of ordering a 2008 spec.B factory equipped with the exact options you want. I'm pretty sure that dealer isn't offering to sell you a 2008 spec.B at $500 below invoice.