We're happy Riverford customers too. We just go for the veg though, and buy fruit ourselves from either the supermarket or our local green grocer - as unless it's apples in season, the stuff in the box doesn't tend to be from the UK anyway. Bearing in mind, we have shops that are only a 5-10 minute walk down the street from where we live. Occasionally, I'll add some fruit onto our veg box order - such as when they had nice blood oranges available.
We started up with Riverford when the quality & price of our local green grocer wasn't holding up to what it had been. Sometimes we get a box weekly, but we often skip weeks if we haven't used it up - it's pretty flexible. I think our 'default box' from when I first signed up is the 'Favourites' one but we tend to change it up every order - varying between Seasons, Roots & Greens (when available in the winter), Favourites or sometimes the Medium Veg box (in which case following, we'd definitely skip a week). We pick the box by the contents for that week - according to our preferences & also looking at how much of it is from the UK, as opposed to from elsewhere.
We found the prices competitive - we were getting more veg in the veg box than DH would get at the green grocer for the same amount of money. The quality of what we get is amazing.
We don't find the amount of potatoes to be unmanageable - it's only about a kilo you get with the boxes that include potatoes. It's less potatoes than you'd buy in a pre-packaged sack at the grocery store. Maybe we eat more potatoes? We usually have a Sunday roast with roasties, and then maybe have mash once or twice a week in addition to that - or else a stew with some potatoes. If we end up with too many potatoes (which is rare), we'll get the Seasons (without potatoes) so we can catch up on our potato consumption.
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We base meals around the veg box contents plus meat from our local butcher, so don't end up having to do much more food shopping that that.
Riverford farms in the UK are in Devon, Peterborough, North Yorkshire, Hampshire & Cheshire - and as much as possible, your veg will be grown & delivered by the farm nearest where you live. They also work with specific growers in Spain for citrus, and specific suppliers for things like dairy, meat & fruits, etc.