Morrisons deliver from a wherehouse not stores so you can't get everything you would in store, eg doughnuts.
I've used and still use all of them, I've even had Sainsbury's and Iceland deliver at the same time.
Iceland do free delivery if you spend £40+ they do next day and sometimes same day delivery. They don't allow you to have more than one delivery pending which, for me, was a godsend at the start of the pandemic. THey also email you with what they are delivering so you know what substitutions you have ahead of time. They also have 'offers' on their webpage that can include free things so I've been able to try new brands for free.
For all of them anything you don't want you just hand back to the driver.
Ocado (although I have not used them for a while) - delivered in bags according to where you store things, cupboard -blue, fridge green etc.
Tesco, deliveries can be expensive if you are doing next day, but are usually pretty good, if they substitute it usually goes 'up' eg you order their own brand cava and it is out of stock you will get the market brand.
They have messed up a couple of times, I ordered a red wine that was out of stock and they delivered white. Then there was the great brie delivery of 2012, I ordered 2 pieces of brie, my carer took the delivery and only after the driver had left did I discover the 2kg of brie.
But there was also the time a couple of years ago we had bad snow so my carer couldn't get to me, the driver took everything intot he kitchen for me and asked if I needed help putting things away (pre covid).
Sainsbury's I can usually get a £1 delivery because I'm home all day so I get a 4 hour slot then on the day they tell me the hour they will deliver in.
When they substitute an item they charge you for the substitution but they also issue a voucher to be used next time.
ASDA - I have not shopped there since I was told to fuck off and got no apology but they deliver to my neighbours every Saturday and they seem pleased (neighbours).