I've been using Whole Foods delivery about 3 times a week, and it's been fantastic, I may never go back. Sometimes the fruits aren't the greatest, but the rate of that is low. Compared to the amount of time I save, it's totally worth the risk.
I have gotten about five orders delivered from Whole Foods. I definitely like that they operate their own service versus using instacart. While there have been some issues with the website, such as losing cart contents (and one would think that Amazon, of all companies would have their site perfect) I haven't had any significant problems with substitutions, quality, or the delivery itself. It was difficult to arrange a delivery slot at first. They seem to have fixed that. The sizes were unexpectedly small on a few things. That's about it.