Unless you really seriously change the cam and other things, it probaby is unnecessary.
You'd be amazed at how adaptive the stock EEC system is.
For example I ran an F cam, TFS aluminum heads, TFS intake, and full length headers and the stock 19lb injectors were fine with just a slight increase in fuel pressure. It was good for high 12's at 108 MPH with no tune at all, and A/F ratio was near perfect.
I finally had to tune the car after installing a blower and larger injectors on top of all that. It was over the 110 MPH range (350 HP) where I had to change injector and MAF parts, and change the EEC.
Save your money.