Ask ko lng po sana regarding tuning problems sa sg..recently i got an sg it tends to go out of tune after string bends...Advisable po buh mg upgrade ng tuners to grovers rotomatic or sperzel?hope anyone could help..TYIA! 
before going for upgrades that you might otherwise not need, check the following:
-stretch your strings after changing them and before gigging to ensure they have adequate "give."
-check your string winding method, use the string locking method to wind your strings under the string post so the actual windings lock the string down.
-check your nut and bridge notch slots. although most big guitar companies have good QC, a few tend to leave the factory needed better filling of the slots. see your luthier for a check on this because uneven slots can cause tuning problems since the strings snag on burrs located within the groove.
-if all else has been done, check the tuners themselves - quality tuners should have a firm feel when you turn them and not have gaps which can cause strings to slip.
