The set I use and have alwaysed used is:
Deoxys - S @ Leftovers
Ability: Pressure
252 HP, 4 Def, 252 Spe
Jolly nature (+Spe, -SpA)
~ Stealth Rock
~ Spikes
~ Taunt
~ Knock Off
This is a pure set-up, suicide lead and I love it as it always does its job well enough to get at least...