As a former spy main with 390 hours of spy, I would use the stock invis with the letranger and the kunai. I would use the letranger and the cloak and dagger with the spycicle for silent attacks and make the enemy paranoid so they get distracted enough to kill spies rather than do the objective. I would use the dr if you are a type of spy that loves to be aggressive, and is good at trickstabs (I use the dr but I am a medium level trickstabber) Remember to equip the amby or the stock revolver depends on the situations, and stock knife if there are too many pyros, and kunai if the situation is calm, and if you like, use the big earner if you feel like the dr is very slowly regenerating and you need it more often.