when is a good time for an ECU upgrade???

[tjf]

so the tib has a CAI and exhaust. Im thinking of headers and a grounding kit really soon (i know they dont make more hp i want it anyway). My question is, when should I think of a ecu upgrade or trip to the dyno, after the headers or wait until i have headers and say a better intake manifold? Also any ideas as to what i could use (mafterburner, apexi, etc...).

Any help is appreciated, thanks and enjoy your holiday :)