SO essentially, you get a good boost in power for 280 (JB+ N55), but if you want lagfix functionality and the ability to play with your settings (although not recommended) your better off getting the Stg 1 tune for $380... More or less
I'll stick to Stg 1 tune... Anyway, Terry said he would add the JB+ functionality to the STG 1 tune, so you would have a Map for Stg 1 and a Map for JB+ type action, so, with that said No need to Trade-In for the JB+ folks. Just stick to what you have, unless you don't care about Lagfix...
I quote to reinforce: "I expect the JB+ will become more popular than the Stage1 just due to the ease of install and lower price. But the Stage1 does have lagfix which is nice. With the next Stage1 firmware we'll load in a JB+ map as well so you can toggle between the two with the laptop and see if you can live without the lagfix."
BMW X5 35i: Boopie Exhaust, Boopie Intercooler, K&N Drop in Filter...
Audi S5 2013 (Delivery Sept 2013): Mods pending review