Had mine done this week, 50k and 5.5 years since it was done.
The old belt looked fine, no cracking, didn't look bad at all. Car is not used much for short journeys as I endure* using public transport during the week. Cost was £350.
*Loud mouth girl the other day on her hands free, talking as loud as you like, 'They effing told me £10 on the electric would effing last all week but the effing thing ran out on Wed', I am going to ring them later and ask them what the eff they think they are playing at'.