My first team was a pair of warlocks (my main is warlock too), and I'll just say it's a lot of fun playing them at the lower levels (only got to 14) having so much firepower. If you time it right you can have 2x imp fireballs and 2x shadowbolts hit the target at the same time. I can't imagine the opening damage you could do once you get high enough to cast more spells that have 1.5s casting time (at max range it takes about 1.5s for a SB to reach the target, the same time as it takes to cast Haunt, which travels a lot faster, so with imps you could have 6 spells hit the target almost simultaneously).

The only downside to playing afflocks Mboxed, is that later on you're going to have a lot of spells to find keybind space for if you want to keep the versatility of the spec. With my new 3x (5x?) warlock team I'm only doing 19 twinks, so my casting bar is going to be a lot simpler than the keybound bar with shift/ctrl/alt modifiers on every button, that I've got on my main.