I was in Holland & Barrett the other day (there's a branch on my route home from work, a handy but expensive hobby), and I spotted a frozen gluten free apple pie in the freezer.
It was one of these http://www.mrscrimbles.com/frozen-fruit-pies.htm (Rhubarb also available apparently).
I considered getting one (more for my husband really as I think he misses such things but I'm usually not that bothered about desserts), but then I saw the price. It was almost £5!
I would consider forking out the money if I thought it would be better than anything I made at home but I am positive that the usual problems that gluten free pastry has would still be there.
I.E You just have to look at the pastry funny and it falls to a million bits and you need a glass of water to wash it down because it's so claggy.
I've also tried their brownies and peanut biscuits and thought they were very dry.
Of course, if Mrs Crimbles wants to send me a couple gratis I'd be glad to road test them for this blog! I'd be especially interested in testing their new Gluten free bread which the website says is on sale in Waitrose and Sainsbury's. I dread to imagine what they're charging for it.