If you add up the price of the equivalent Defi's / SPAs up, then yes the Stack is more than worth it, as you get many more features (odometer, trip, fuel level) on top of the features that the alternatives come with, which would not be available with the SPAs or Defi's. The Stack does everythin in one gauge and so is also easier to monitor (if a particular item exceeds your pre-set limit, it flashes a pop-up in front of you to high-light this), as well is install (goes straight in the dash, so no problem with trying to find a home for a kazillion gauges ).