There are already a lot of kits out there on the market but if you like it or not...be cautious.
Regarding removing the VTG chargers: in my opinion, this is a lame thing to do. I'm also not sure if this is a wise thing to do since the motronic software who directly controls the VTG chargers is also controlling PASM and PTM to some degree. Removing the VTG chargers and using old fashioned chargers instead is actually good for gaining more power but it is actually destroying the whole engineering of the car since PASM and PTM would actually needed to be switched off or at least crippled in their functions. I doubt that many tuners can do such a thing (it would require a lot of knowledge and testing), so I would NEVER buy a 997 Turbo which has been modified this way.
The question is whether such a modded 997 Turbo is actually a 997 Turbo anymore...or just a 996 Turbo in 997 Turbo outfit.
People are usually blind when it comes to power, they don't use their brain. The VTG technology is one of the major breakthroughs in the 997 Turbo, along with PTM and the electronically controlled viscous coupling. Removing the VTG technology from the 997 Turbo renders the whole engineernig job of Porsche actually obsolete, this is really a bad thing to do in my opinion.
With the current VTG chargers power upgrades up to 550 HP aren't a problem. 550 HP (if they are REAL 550 HP) are enough for 0-200 kph in 10.8 sec. and 0-300 kph in 32 seconds, in my opinion this is enough. If somebody wants more, we're talking about substantially more money and extreme mods which actually can't be removed too easily.
And another thing: tuning the 997 Turbo improves performance mainly in the upper 100-125 mph speed range.
So in my opinion, tuning the 997 Turbo in speed limited countries is pretty much senseless. Unless you drive to Germany from time to time.
For track racing, I'd invest the money in better tires (Michelin Cup) and better driving skills (driver ed events, maybe even personal training).
The only REALLY needed thing regarding mods is actually the exhaust system. The exhaust sound is really lame and I wouldn't accept it longer than necessary.
BTW: apparently, one or two tuners are planning using different VTG turbos for the 997 Turbo to achieve a power gain. These turbos are made to specs by Borg Warner, however I don't have any details yet and it may take a while. Meanwhile, I suggest you guys keep your power hunger/greed under control because what I said in the past is still valid: playing the guinea pig can be very very expensive.