Personally I wouldn't trust a plug in unit. Engine mapping is an art and it's pretty rare that a 1-size fits all approach will be ideally suited to the hardware or the condition of your engine and turbo.
I've made enquiries with CC Tuning because my Angel Tune is a bit too aggressive at low revs and the car creates a serious smoke screen on full throttle. I've had the MAF changed and that improved things but didn't eliminate the smoke. I'd take it to Angel but they are too far from me.
The guy from CC Tuning responded to my email very quickly and seemed confident that he could eliminate the smoke and improve the map. But first things first, my car will need a new rad and other issues sorted before I can put it on the dyno. I'm still undecided as to whether or not I'm going to keep my car (as my other thread's show, I'm looking at 159 SW's), but if I do I will get it remapped to make it more balanced.
156 2.4 JTD 10v Veloce with Angel Tune (180bhp)