It was stage 2 for around 55,000 miles. It was launched maybe 10 times the entire time I have owned the car. Pretty much normal driving and sometimes would drive it hard but certainly not beating on it.
Money is my limiting factor as well. It cost me $3300 for a rebuild. If it blows up again I will just charge the full IPT trans and be done with it. The guy who rebuilt my transmission used to do all the Subaru Road Race team transmissions so I am not too worried.
Trans cooler won't hurt no matter what mods or stages are done. The stock cooler runs through the radiator.