That is true, in theory. However, assuming you keep your mods mild, like a CAI and a tune, if you need to bring it to the dealer, you can just replace the stock airbox and re-tune. I was able to swap the CAI back to stock and re-tune in less than 15 minutes, though my S197 was already out of warranty by the time I bought it.
Also, some dealers are mod friendly, and won't make a big deal over things like CAI and tune.
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