i have the ets 3.25 incher. it was the second mod i did after an intake, and it made a very nice difference in overall acceleration. it will still heatsoak like any tmic but sheds heat way faster than the stock unit.
i did a lil test before i install the ets. i fired the car up and let it warm up to idle and touched the IC and it was pretty dam hot. blasted down the street jumped out and it had cooled a lil but still hot to the touch.
after i installed the ets i did the exact same thing. after the car had warmed up the IC was hot to the touch. blasted down the road to the same spot and pullled over to check it and it was actually cool to the touch. seriously, i was shocked. i expected it to be cooler and shed heat faster than the stock unit but not that much.
i've even pulled over to show my freinds and at first they'd be afraid to touch it thinkin its real hot, then they do and they are equally impressed.
its absolutely a worthy investment from a performance stand point.