E-Manage is like $400, but the E-Manage Ultimate (the one you want) is $600, though you can find them on sale for like $5-550. The new fangled AEM FIC is the same price range. But you put in the cost of the wide band o2's you will double that (obviously). So total out the door should be $11-1200, but then you have dual wideband's, which is great.

Also may want to wait and see what LantanaTX's Mercedes tech can do with unlocking the ECU, if he can do it then a SRT ecu in a standard X-Fire may be the way to go as well for boosted apps.