ang spyder calibration di naman ginagalaw ang service menu IMO....
There are certain displays which allow you to adjust the RGB bias and gain (often, there are different labels for these like cut/boost) via the ordinary User Menu, not just the Service Menu. You need these controls in order to calibrate the gray-scale of the display.
I know that the Panny pj's allow this. In these cases, you can do the Spyder calibration without entering the Service Menu. Otherwise, you have to use the Service Menu. D ko lang alam if the Panny TV's allow these adjustments.
The Service Menu will often have these controls as well, but with much more refined steps. Kumbaga, if the ordinary menu is -10 to +10, baka -50 to +50 ang Service menu. Ergo, it is better to use the Service Menu for calibration.
In any case, if you use the Service Menu only for the RGB bias and gain, there should be no problem whatsoever - I always do that with my own Sony pj. HOWEVER, there are many parameters contained in the Service Menu and there are some parameters which you should absolutely not touch, else baka masira ang display or shortened ang life. That's why the manufacturers will naturally be wary about people entering the Service Menu.