Meh, bagless have their downsides, but in my personal *opinion* I think they're fine. Dumping the dust into my garbage can is not a dirty ordeal at all, it's quick and all the dust just falls to the bottom. It's far more unpleasant dealing with an antique shake-out bag, now that has to be done outside because that'll give you a face full of dust. I don't have much experience with disposable bagged vacs, but I've thrown away a couple vac bags full of dirt, and if you're not careful and squeeze or shift the bag, even a little, it'll blow the dust right out of it, and that'll give you a face full of dust.
So, really, there are pros and cons to either system. To add something to the list:
-> Bagless vacs need to have their filters cleaned or replaced regularly.
Actually if you're shopping for a bagless, I'd recommend checking which one has easy filter access, and washable filters.