I have an upright, Dyson DC07 Allergy Hepa Filter blue turquoise upright vacuum cleaner. I bought it in 2004, but it's only needed one service in all the time I've had it, which is over half the time I've lived in my current home. It picks up really well, but it is heavy (good thing I live in a flat, really). I bought a V6 mattress last year in the Lakeland Black Friday event. It doesn't have the long pole, but I love it to bits. I vacuum far more now that I have this little, powerful gizmo, that I can whip out for a quick attack on everything from crumbs on surfaces, cushions, curtains, lightshades, the floor... just brilliant. Both of these pick up loads of stuff, and if either should conk out, I will probably go for another Dyson to replace... preferably just one device. Realistically the V6 mattress isn't a replacement for my upright, but the next one, if it has a stick, probably will replace it.
Based on my own experience of their vacuum cleaners and the service, I think Dyson's are a good bet... but it really depends what you are looking for: power, amount of usable time after a charge, ease of use, ease of cleaning (the machine itself), the efficency and effectiveness of the cleaning.
I think I get the best of both worlds by having the plug-in flex-based upright, and then the cordless handheld.
Be aware that you have a boost button giving you more power, but you will significantly shorten the usable time. As I use mine for spot attacks, it's perfect.