I've been using Litchfield for many of my projects for over 12yrs now and for me, they have never let me down and always delivered the goods.
My previous Subaru's have delivered the goods, my previous A45 with their tuning achieved the quickest 1/4m in the UK and so has my current Stage 2 RS3 (like for like mods versus anything else that has ran in the UK down the strip).
Dyno's don't tell me everything..... trap speeds and ET's down the strip tell me a lot more.
My RS3 is now going through a more extensive upgrade program over this Winter (with Litchfields and their technical partners) so will be interesting to see how that goes when it hits the strip again in 2018.
We all have our preferred tuner(s)..... it's a choice. I've heard horror stories about all of them, and whilst I would never dream of stating Litchfields were the best, they have always done me good. That's all I care about.