You forgot Sebo which, as anyone that knows anything about cleaners will tell you, they are one of the best you can buy.
If you want a cylinder cleaner (which to my mind are superior) then Sebo K3 Premium is a superb machine which gives you the best of both worlds as it has the pukka power head on it.
I've not yet used the new upright Sebo cleaners but some friends that sell them are more than a little impressed by them. They have a lot of clever stuff built in and are, according to all reports thus far, outstanding to use. TBH though, it's what I expect from Sebo as they don't seem to compromise much.
Bagged v bagless is a raging debate, still after almost 20 years since the first Dyson ever appeared and the Great British Public seemingly became fascinated with watching all their dirt swirling about in a plastic tub.
20 years later and... nope... I still cant see a commercial cleaner or one of what are considered to be the best domestic cleaners using a bagless system. Even if I knew nothing I'd wonder why but, the reason is simply that they are inferior in terms of performance.
People love the idea that they don't have to buy bags, but the problem just changes, it doesn't go away. With bagless you either have to buy and replace filters (a lot) or clean them (a lot) to keep the thing going, you also have to tip them out more often as well. Most people don't and the performance tails off, dramatically.
But people buy into the hype. Some even will tell you how brilliant their Dyson or whatever is but, as soon as they use a good cleaner again they'll never go back to a bagless one.
I'm sure you get the drift by now.
As to the cost of bags, I have a reasonably normal sized home with two young kids and we go though a pack and maybe a bit of bags a year. It's really not that expensive but a lot less messy than mucking about tipping dust out a bucket and the house is cleaner.
Buy the Miele or a Sebo. If it was my money, I'd go with the Sebo over all others every time.