Although Wynn managed to soldier most of the cracks on the stock K03S turbo housing, there's one particular spot he can't is somewhere near the compressor shaft. While the engine is boosting fine now, the cracks will come back hunting me sooner or later.
The most easiest and 'worry free' upgrade would be Borg Warner K04-001 or OEM-ed from RP and CTS for less than USD1k. There won't be much of increase in hp but because of slightly larger housing, the power deliver should be more stronger and linear from mid range onwards. Pity that it is not water-cooled to disperse heat more efficiently.
Besides the the turbo, I definitely need to source for at least 380cc injectors, 3" MAF, custom remap and maybe after market turbo manifold. It won't be soon I hope...
Image taken from ECS Tuning USA