Simon, you know the one word I have for you: Dinan. I'm not dismissing these other products, and some of them feature more aggressive tunes, but it's obvious that you want a refined tune, not a fire-breathing track setup. Dinan tunes are expensive because they are extensively tested and warranteed. If you are not a seasoned wrench-turner or serious hobbyist, why drive yourself crazy with all the maps and variables offered by these products, especially on a brand-new car? And I am very dubious about the claims I hear regarding the extent to which some of these tuners have cracked the ECU codes for the most up-to-date BMWs. I am
not flinging mud at any of these products, nor questioning their integrity or denying their usefulness to a specialised type of consumer; I'm just saying that you have to have to have a certain level of technical commitment and a high tolerance for risk to subject yourself to the enormous potential downside. The Dinan S1 tune makes my 228i as fast from 0 to 60 as a stock M235i, if not a tad faster, and has never given me so much as a millisecond of anxiety; no hiccups, no CELs, no non-linear power delivery. And if I had a 235i, I would have sprung for the Dinan S2 by now, which will get that car from 0 to 60 in 4 sec flat. If you're not an autocrosser, track rat or drag racer but just want a really well-sorted DD, what use could you possibly have for more than that?? Take a look at this video; it's about how to balance performance with stability when making tuning products for expensive new cars.