This question can't be answered effectively without more information regarding your trading style. Most scalping of highly liquid fast moving products would require orders that are essentially market orders. (That could be a limit order that is far enough in the money so as to actually be a market order). The reason for this is that, if you are really scalping, you won't get hit a lot of the time unless you use market orders. If you are talking anything over 2-3 minutes, I don't think that qualifies as scalping. Scalping is tough and not many people are successful at it, largely due to commission costs.
I don't trade futures, but for equities, using limits help when you're either gaming support/resistance intraday and you stack orders around those levels, or when you have a pre-established target for entry/exit.
Two things bother me with a limit order: 1. I don't get filled, market leaves without me. 2. I get filled, market runs me over by some distance.