Choosing a vacuum cleaner

I changed the bag in my vacuum cleaner at the end of a hoovering session. When I came to use it last weekend I could hardly get any suck out of it at all.  I can't work out why, though my mother suggests the filter, which I can't get at

Although I'm not keen on housework, especially hoovering which makes my back ache, I have the first Transition Leytonstone recycled craft meeting on 13 March and feel I ought to get rid of some of the dust and cat fluff first!

So after work today down to John Lewis looking at vacuum cleaners.  Stood there for ages trying to decide between a John Lewis one and a Miele one.  The John Lewis one was nearly half the price, slightly lighter, bigger capacity. The Miele one was Which Best Buy and used less energy. I went with the Miele one, but don't know I made the right decision.

Fourteen years ago I got a washing machine and choose one that was better energy rated but more expensive, but it only lasted 4 years.... Its less green replacement has already lasted 10. Time will tell with the vacuum cleaner.