RYBCC -- Well said!

But to add. Many of us if not all have seen Roman's car and are not dissing his work, but in this case you are comparing apples and oranges. His system is a complete custom job. How many hours did he spend manufacturing his turbo manifolds? intake manifolds? I'm sure if I was offer a tuner $20,000 they would still need more money to do a job like that.
The TT kit is just that, a kit. We are not touching anything else other than the engine. If we wanted to we can get to the point of the amount of boost and HP that is in Roman's car, than we can quite easily build on it.
As well, if you look into it a cast manifold is much more stable than tubing welded to a flange. I've been researching do a turbo set-up for about 3 years now, and many threads that went into great depth on the subject, and shops that do nothing but turbos all came to the same conclusion regarding manifolds. Once you weld a piece of metal to another piece of metal it warps. You can have it ground to what is perceived to be flat, but you will always have issues, if not with that then in time with fatigue with the welds.