Terry @ BMS also did some IAT comparisons with their filter and it showed almost no difference between the stock unit. I can't imagine the aFe being worse, especially with the heatshield/cover available. If you're planning to buy an aFe intake, then they do sell a box if you are worried about heat.
I don't believe Dinan has cracked the new ECU yet, or else I'd consider it. But I have not seen or read any issues with the JB4 though. And at this time, the JB4 seems to be the best dollar to horsepower unit out there that actually works. Once the new ECU is cracked, I might switch. But for now, I am okay with this and along with the other thousands of the boosted BMW owners out there that use the JB
.