I have done the grocery game for ove a year now. I love it! I'd be curious to hear other people's opinions also just to make sure I'm not enjoying what I think is a good thing just to hear others say it is a scam (funny).
I don't know where you live but I know that I have a few discrepencies every now and again on my list but I think that is because I am on the outskirts of all the major cities around me.
Let me know if you want more info. I can tell you that I have never had any problem with customer service when I needed to take a break and adjust my account.