A Plug and Pray ecu would be of little, if any benefit unless you modify your car exactly the way the designer of the map intended. The chances are that you'll run slightly different bolt-ons, have slightly different internals, different atmospheric conditions, and different god knows what else, to what was intended for the particular map.

I don't like the idea of being bound to one particular combination of components one little bit, and this is precisely the situation you will be placed in if you forked out your hard earned on a program designed by any of our fine japanese bretheren.

My advice is to find a tuner that has proven themselves to be a competant tuner, with a good record, and proven street and track results and use them to tune the ecu as per your individual requirements.