Well...
...I have this attitude about my Paul that it must always be the strings, NEVER good old Les.
So, I give the saddles a bit of attention and, sure enough, there must have some tiny burrs. I'm up to two weeks on this set.
I had a FR on an Ibanez Fako-caster w/locking nut. It did stay in tune pretty good. POS guitar though.
How you doin' with the GNX? I'm having a blast with mine!
(PS, my real Strat never breaks strings either until they get well past changing stage anyway)