Golf 4 1.9 TDI Downpipe - ASZ Engine

I want to have a new exhaust system made for my Golf, from the catalytic converter onwards, using stainless steel and with a 2.5" pipe diameter. I have a question about the design of the downpipe. Would it be more advantageous to increase the diameter directly after the turbo, before the bend, or only after the bend and before the flexible section? With Milltek's downpipe, the diameter increases only after the flexible section.

The solution was determined by the design constraints. The extension must follow the curve because otherwise, the flange cannot be attached.