We've been using them for about a year.
They don't have a wide enough range for a full weekly shop/ocado replacement, although they do have a pretty good range of tins and store cupboard items.
But their main selling point is that their meat and dairy are fantastic
The veg is also great, but a lot more 'rustic' than supermarket food - untrimmed, still with mud, etc
It doesn't bother me, but it might for someone people who are used to lovely neat supermarket packs
Their delivery drivers are really friendly, and if you go for the 'no packaging' option, it comes in cool bags which they then take away, so you aren't left with a cupboard full of carrier bags.