Lootas!!!!

I freakin love lootas. They are the best long range shooting unit Orks have to offer. I use them to take care of light vehicles, heavy/light infantry, special character assassinations, and most flyers.  

I usually have 2 squads of 10 in my army. I would like to carry 15 in each but I don't have the models yet (being that GW sells them with 4 lootas and 1 mekboy per box) 

Having 10 lootas gives me from 10-30 shots per turn. On average a third of these shots hit. So at S7 against pretty much any standard infantry I'll be wounding on 2's. This will usually take out  2-4 space marines, 1 out of 5 terminators given some luck, and an entire squad of IG infantry. And since I have another squad waiting to let the shots loose they can handle the rest or weaken another squad. 

 

Using these guys in synce with the rest of the army is really important. With a 48" range they can reach a good amount of threats to  the main horde of ork boyz. Weakening the each enemy squad before you plow through with the 30 boy squad. 

You could also be crazy and put the 2 squads of 10-15 in battle wagons and just drive around the board snapshotting at the enemy with 15-45 shots hitting on 6's. Snapshot 6's aren't that big of deal considering orks usually hit on 5's. I say it's still worth it. Just realize that once your battlewagons get targeted and armor penetrated, you will lose half of those Lootas. Anything that can damage a battlewagon more often than not will blow it up, causing the S4 hits on the entire squad inside. 

  UNLESS you play this up: put mekboys as your HQ's and give them Mega Armor so they can save you lootas for one more round of shooting. This can lead to a ton of other things like 2 Deff Dreads as troops, and a so on an so forth.