Yeah, I'm gonna go with everyone and say really think long and goddamned hard before you decide to do this. If you still want it in 6 - 12 months, go for it ...

As for the pain and size; I also agree with Rye! Don't get something too big (especially something that's going to be all black O _ O) on a part of your body that's really bony or nerve-ey unless you're sure you can handle it. My first was on my inner forearm and is about the size of my fist and I was really taken aback by how painless it was. However, the most recent one I got (script across my collar bone [original, I know ]) was painful as ; if I had gotten that one first I'm not sure if I could have handled it.