I used to do 6 SNG's. Some thoughts.
You won't be able to find the best spots to steal on all tables at once, especially as you approach the bubble.
Space them out so that you dont end up 3-4 handed on all of them at once.
Play tight, small ball poker and dont do anything stupid before the bubble.
You won't get nearly as many reads, but keep playing solid poker and you should get somewhere.
I lost my stats, but I was somewhere around 60% in the money when I played 6 tables at once, but my first and second place finishes dropped compared to 1-2 tables where I was in the money about the same percentage, but more first and second place finishes.
If you are the type of player that gets bored and makes stupid moves because of it, multi-tabling can help eliminate some of those as you dont have time to get bored