Will a tune without any other mods improve my performance?

[prpilot]

I have a 2006 Mustang GT, all factory. I've read where the factory airbox/filter has very good airflow, so that a CAI doesn't improve things too much...maybe 8 to 10 HP at most (Which is good, don't get me wrong!). But how much of a performance improvement might I see with just a tune?

[mikel]

The tune alone will add about 15-20rwhp.