I'll happily start the ball rolling with Abbott Racing.
I've had cars tuned by them for a long time know with first being a 9k CSE 2.0lpt they tuned to around 195hp. Lovely and smooth to drive with excellent pick-up with small turbo. I then progressed up to a 9k aero on which they did ECU, downpipe, exhaust, suspension etc and the car flew. £ for lb excellent. Sold that to enthusiast with 18k on it and bought my first 9-5 which was one of the first estates in 2.3t SE guise 185hp. Abbott's did ECU, inter cooler, hybrid turbo and so on and car went like the wind. They also did engine re-build which was faultless. And lastly my 03MY aero auto estate which they tuned to 275hp and 430Nm torque. Car was incredibly quick and yet a smooth drive. Fuel economy also improved. Only reason sold was no longer long distance drives each week so economy was no good around town at about 23 - 25 so bought a 55Reg Vector Sport 2.2tid which does 44 around town. Would have had Abbott's do the ECU but adding up travel of 3hrs round trip and price Hirsch had discount deal so did that but would have done Abbott's if near enough.
I can honestly say I have never had a single problem with anything Abbott's have done and Ed's team are so enthusiastic beyond belief. Pleasure to deal with.
That's my two pennies worth