I got one from eBay for £13....then £7 for the DashCMD app. You can configure your own dashes with any data you wish...RPM, MPG, oil temp, boost, speed, fuel rate, est BHP, gear change points etc. You can also log all the data and replay your trip.
You can also read errors and reset them. I've found this very helpful...not so much the dashes...found them more of a gimick...but I'm a techie so I like to fiddle [emoji16][emoji15]