We tried Morrisons for a while. I agree that the food was good, however their stock control leaves a lot to be desired, we frequently had loads of missing or substitute items. So for example, you'd order five meals, but out of that you'd have e.g. two main courses missing, puddings/starters substituted for duplicate items etc. So you'd end up having to go shopping a few days later to backfill the missing stuff, meanwhile getting bored of eating the same puddings.
It's a shame because as I say, the food quality seemed better than Asda and Tesco, they just couldn't deliver it all.