Staying in tune depends more on the parts. Tremolo bars if used often will detune the guitar. The tailpiece is also important. TonePros makes a good locking tailstop. The tuners are very important. Grover probably makes the best locking tuners. The strings also need a period of breaking in after the guitar is restrung, so the guitar might need to be fine tuned a few times while playing. Floyd Rose makes bridges known for keeping in tune for a long period of time. String tension will help it stay in tune, several companies like Schecter make through body strings which increase string tension. I would say stay away from a tremolo or lock it down when not in use with a tremolo-no.