The budget lifts use spacers to gain lift. In the front, this can be either a spacer that mounts on top of the strut (Rough Country lift) or a spacer that mounts inside the strut (Daystar). For the rear, it is simply a coil spring spacer that sits on top of the spring. I would suggest goin' with the RC 2" lift, as it truly levels the front, unlike the daystar kit. The best part is, the RC kit only costs $150.
The OME kit provides lift with the use of replacement springs front and rear. The struts are not needed to gain lift, as it is all in the springs. The springs are the same length as stock, just higher spring rates I believe. Because of this, you can just order the springs and use your stock struts if you want to save a bit a money. Many just upgrade the struts to replace worn stockers.
On a side note, is your username a reference to the rap group Gangstarr?