I have APR's DTR on my Mk7.5 R with an upgraded intercooler. It was close to 90 degrees in NYC today. I came from bone stock a few weeks ago, and was bone stock since August of last year. Upgraded intercooler is a necessity when adding additional power, whether it's track days, pull after pull, or even going to the grocery store and back. Imo, running an upgraded turbo + tune on a stock intercooler is like putting on two N95 masks and going for a jog on a warm day.
Another former R owner had the DTR + upgraded fueling on a stock intercooler and he felt like his car was sluggish. Your car won't trail off with an upgraded intercooler. You'll be able to sustain that power practically every time.