I have had the Dinan Stage Ii tune from the beginning. It is very much worth the money. I find it ironic that guys who spend the money it takes to buy a BMW go cheap on something as important as a tune.
Stop making this a tuner value debate as this is not the situation. Dinan is the only tuner willing to out their money where their mouth is. Why do none of the other tuners offer any kind of warranty? The reasons are self evident. Dinan is more conservative than other tunes in terms of its horsepower but not its torque.
If you don't mind burning out your engine, or needing to prematurely replace turbos and others key parts of your powertrain by all means go get a more cost effective, high boost tune. But isn't that what an M3 is for?
Active Autowerkes makes a great tune fir the N55 as well. It is cheaper than Dinan but allot more than the piggyback. But has no warranty. Cobb will come out with one in the similar price range I am sure.
2011 335i M-Sport Sedan | MHD Custom Tune by Wedge Performance | ER CP | Catless DP | Koni Sport Dampers l Eibach Pro Kit Springs | M3 Suspension Upgrade l BMW Performance Exhaust | BMW Performance Front Grill | OEM Euro M-Sport | 19" Volk Forged Performance ME's | JL Audio HD 900 | Morel Hybrid Components | JL Audio W3v3