To be honest I would only ever get my dsg box done at a main dealer,
It's not as simple as a normal transmission fluid change by any means, it does have to be done via 50/52 as the oil in the box has to reach a certain temp, and mainly they take 6L and it HAS to be proper dsg oil, I had mine done whilst having my mechatronics done under warranty
I can't really say it feels better as it's all now different lol, it's nice to get it done tho!