I've had about 15 supermarket fruit trees over the years, both in my present home and my previous one. Maybe I was lucky but they were superb, and only cost about £6 each
I have 6 supermarket apples, plums and a cherry here now, and they are growing well since planting a few months ago, I wouldn't expect much in the way of fruit this year or next.
Of the two 'posher' supermarket apple trees, one has loads of fruit on it, the other is a twin variety and ahs nothing on it at all, I don't even remember flowers on it
But what I'm REALLY looking forward to is the lower bunches of elderflowers to come out so I can get my cordial and wine started YUM!!!