The statement about allowing "Dinan to void my factory warranty" just isn't true. While Dinan offers a parallel warranty, it does not void your factory warranty. Anything that Dinan's software upgrade might be responsible for will be covered by Dinan; anything else is still covered by the factory warranty. I've had Dinan software in all 3 of my 3-series cars since 2001, and I have never ever had a problem with warranty or any other issue with my cars. The dealers I have worked with sell and support Dinan, so that may be why I've been problem-free as far as coverage goes. Besides, Dinan's tune levels (aside from S3) are not likely to cause any real issues. They never have for me, including the S3 I now have in my E92.
That said, as soon as S2 is available for the F30 335i, I'll be having that installed on my F30 M-Sport. The PPK will add maybe 20HP; the Dinan software will add quite a bit more for nearly the same price. $1700 for 20 hp/26 tq and some stickers or $1995 for 55 hp/100 tq? Seems like an easy choice.
2013 F30 335i M-Sport 8AT/MPE/MPPK, 2016 228i M-Sport Cabrio 8AT