SO8 said:
Was that bought direct or from someone in the UK ? I am guessing it is another handheld type device or software and a cable from a laptop.
Hi, purchased direct from ESS in the US and shipped over.
There is a coded USB module that plugs into the diagnostic port which locks to the ECU. You download your current map and other diagnostic data onto your laptop and send it over to ESS, along with details as to the type of fuel you run and any other mods that may have been completed. They then send you back two maps, stage 1 and stage 2, specifically for your car which you load up from your laptop.
I spent quite some time researching which system to go for prior to purchase, as they are expensive compared to other options and don't have the highest power output claims, but the reviews globally from those using ESS on the N54 engine were very positive in terms of performance and drivability. It's very easy to go back to the stock map, plus you can run stage 1 in the winter if you still want the drivability but not the 390DIN peak power.
At the time back in 2012 there were also other UK members on the forum who were running the ESS maps with positive feedback.
We've had no issues at all over what is almost now 3 years of running with the ESS maps.