I have had my one and only 180 for over 9 nines and done around 80k miles in it. Those miles have been a mixture of pleasure, commuting and track days. It has never let me down and even on the occasional commute it gets 'used' on the country lanes. My engine has been remapped so the AFR at high revs is optimised. On track it gets used as a race car should, I never back off and it gets the beans with no ill effects, I have total confidence in it. On the road I hardly get near the limiter, same for the track as well, as peak power is below the limit for me. 6k should be sufficient tbh. You will know when the time comes, depends if you like the noise.