Keeping the customer happy

I have a 105 long cage rear mech on my tandem which needed replacement. Unable to obtain the 105, Cyclelab Fourways offered an Alivio 9 speed MTB mech which was believed to have the same travel per shifter click. Unfortunately after taking the bike out for its first ride, it was clear that there was a difference and gear changes were not smooth as they should be. On reporting this to the shop, they straight away agreed to source the 105 long cage mech which arrived some days later. No arguments about taking back the Alivio.