A tolerance really shouldn't occur with SX, as the "stims" in it don't force the body to build up a tolerance like caffeinated supps would. Some may find their sweet spot after a few days of experimentation, but it's really a good idea to start at 1 for a bit and go up if you feel you really really really really need to.
To answer the OP, very bluntly, NO!! Mixing in any sort of "dirty" stim will really give you an "interesting" experience. White Flood is good stuff, used it myself, and I know what kind of a rush it gives. Combining that with SX at ANY point during the day will not only take WF's stim effects to a whole new level (in a bad bad way), but also extend the amount of time that SX works in your system. An additional stim taken at any point after dosing SX that morning will reignite it and start the whole thing all over again. If your dose of SX lasts 12 hours, adding in WF will up that. You could be up for 15, or you could be up for 25-30. I don't know, and eventhough I'm insane, I'm not silly enough to try it (again).
:nutkick: