Some days I get exactly what I ask for really quickly, when other days I'll have my shopper switching 25% of my requested items with alternates (some of which are wildly off base).
My biggest frustration is that it seems like the shoppers aren't intimately familiar with my local grocery stores. I'll request an item that I know exists, they'll swap it out for something completely different and not what I want, yet if I personally go to the store, I'll easily find the item I requested.
Prior to the change we'd get a call to confirm all substitutions, the produce was higher quality, and they call to let me know they were on their way.
After the change substitutions happened with no warning till it was delivered if they even marked it as a substitution. Anything large or not quick to get would be marked as "not available", such as soda or specific cuts of meat that required talking to the butcher. That one isn't even a speculation as I'd have to go down to the store and get the items myself if I wanted to prepare my meal I had planned.
The shoppers would also knock on my door and drop the bags on the floor at best. I had several occasions where they just left the bags without knocking or calling and I had frozen items dethawing outside.
All in all I felt like I was paying extra for a product that was inferior to the results of me purchasing the items myself, and was no longer convienant as the substitutions, low quality produce, and wrong cuts of meat were leading to me having to go to the store myself after every order.
If they could get the quality back to where it was the first two years I would have been willing to pay 50% more because it saved so much time, but I don't think they are headed in that direction