dinan is covered in bmws warranty...but dinan products are expensive and is mediocre when it comes to performance.
if you want software, i strongly recommend the Shark Injector. It 'may not' be covered under warranty but you can always transfer back to the stock software anytime you like all by yourself.
to get into detail, bmw cannot void your warranty because you have aftermarket parts. Now if you got a problem with your car and they prove that the aftermarket part(s) caused the problem, they can void that particular warranty.
Example1: If you get an engine light: And the only aftermarket part you have are RIMS, they cannot say they will void your engine warranty because of your rims, cuz in reality, rims have nothing to do with the engine.
Example2: If you get an engine light: and you have an aftermarket intake, they 'can' void your engine warranty if they prove that the intake caused the problem. This does not mean they will void the whole warranty all together.
Most dealers will be nice about aftermarket parts. Only the anal dealers will void warranties. My dealer in my area actually promotes aftermarket tuning.