Just an opinion: I wouldn't recommend JB4. I have driven several cars with JB4, but not Porsche's.
The point of a JB4 is that it's generally used when a DME (ECU control module) has yet to be cracked or hacked. Once the technology is out for a proper ECU tune, JB4 gets tossed out the window. The JB4 is a piggyback unit that controls limited parameters like boost and timing, but it's not smooth. It's essentially like an outside alien or parasite that will control a few functions to increase performance.
It's a great idea when there's nothing else available on the market to increase power for your car. This was a problem in the BMW community when they launched the E90 and F30. There were no alternatives, because no one was able to crack the updated BMW DME's. Once the DME was cracked, several tuners popped up with proper ECU tunes, and everybody who was able to (financially speaking), switched.
Now if you go on to a Beemer forum and mention you just bought an M3, 335i, 328i, etc... and you plan to modify with a JB4, you'll have 15-20 different people explaining why not to go this route.
I have a VR Tune from Vivid Racing. They have 2 types (a piggyback style that's similar to a JB4 and a proper ECU tune), I of course opted for the ECU version. ECU tunes tend to run a bit more seamless and similar to OEM drivability.
Yes, as it stands now, you would have to remove your DME and send it to a tuner to crack. I'm not sure if Cobb or someone else has come out with a flash tune for our cars that we can do ourselves. But I'd at least take the time and look into it and see if one is available yet. In time, we'll have several flash tune options for our cars that you can download on to the car yourself. But being a new platform, your options are a bit more limited.
I would recommend sending in your DME to VR or Eiserman, maybe even waiting till there's flash tune (if you're not comfortable sending in your DME) or doing a little bit of research to see if a flashtune is already out (I haven't looked for a while, so My information might be a bit outdated). I'm just simply trying to give you an alternative to a piggyback unit...