Is it flash or piggy? If it's piggy you can just remove it each time you visit the dealer whereas a flash you'll lose everything when the dealer flashes over it. Also for the price it looks like a steal!
In terms of warranty, BMW will try to stuff you whatever and whenever. I have a 135i and throwing a procede was probably the best thing I've done to it. I wasted to long to get over the warranty crap, now looking back i should of done it day 1. Also a tune shouldn't harm your car - look after it well mechanically and everything should be safe and sound.
Only downside is I haven't heard of that tuning company before. Most of us are either with procede or JB on our n54 and the support team is amazing. Try asking Wassell2381 on the forum, he's got the same engine so he should know a lot more.
