I think most people on here really need to step back and realize something...
YEAH, its is not the 100% perfect and ideal way to go, BUT, this is the most affordable kit on the market, keep it simple so it works for everyone and makes solid power for a good price seems like a pretty smart buisness model to me.
until you have built your own turbo kit, or maybe a few, you really shouldnt comment on this stuff. going from a pocketed DP like silbers to a divorced type setup, there is easily 3-4x the time and effort into making a divorced downpipe(i have made probably 20 different ones personally, so know how challanging it is!).... for a production kit, a 2.5" DP with pocketed flange works great and is easy to replicate. when you sell 100+ kits a year, ease of production is paramount.