I think it depends where you live, I used Coles when we lived in Sydney and had to stop because they would turn up over an hour before the allotted times without a phone call, I had missing items, off seafood, they were awful! I changed to Woolworths and they were perfect, no problems at all.
Now we have moved a few hours north and I continued to use Woolworths for about two months, but each fortnight there would be something missing. Problems ranged from out of date food, delivery drivers turning up at 7am when the allotted time was 8-11! Now we ate back with Coles and everything is great, no problems at all! I must have really bad luck!
I do prefer online shopping though, I don't drive so it's alot easier buying online than taking the kids on the bus!