I've not played with my EA82T very much yet, still need to sort some codes before I start driving it hard.
On my EA81T (custom SS header, catless 3" downpipe, 2" exhaust w/ Flowmaster muffler, stock otherwise) I've never had an issue with overboosting. Boost starts building at 1,250 rpm and I've got the full 7 psi by 2,000 rpm, so no real turbo lag to speak of.