Do the JB4, you'll love it. I'd say go with the new G5 ISO however if you want to save some cash and stick with the older G4 board i have a 15ohm for sale since I just upgraded to the G5 ISO. Either way definitely do JB4, that makes the biggest difference out of all the mods and you won't regret it.
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E90 335i xDrive 6spd, Nav, Prem, Cold Weather, & Sports package - Msport Conversion
MHD w/ Wedge Flash, MMP Inlets, VRSF DP/FMIC, ER CP, SteveAZ LPFP
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