Yup, I've been told the same. A fresh standard clutch on a 150 Mjet engine (doesn't matter if Fiat or Alfa etc) is reliable to 180-ish so long as you don't drive like a tosser. Really it's more about the torque which apparently will go through the roof - I don't have a figure to hand, but if you say power is up by (say) 30% then torque increase is around 50%. And that's a lot.
I had no clutch issues with the Stilo JTD which went from 115 to 155bhp and a substantial hike in torque but I do know someone else who had a 150 Stilo mapped and his clutch gave up the ghost a mere 2k after the mapping session. Mind you, the car had done 60k miles and was on the original clutch.
You pays yer money........