Hi,
I use mobile broadband, from 3G.
It is very convenient if I want internet access when visiting relatives who don't have it, or I want to surf on my ol' lappy downstairs when my P.C. is upstairs!
It is faster than dial-up, but not as fast as "normal" broadband, although you'd need to check that it is available in your location.
I pay £15 pcm for 15gb download limit - I use on average about 5gb pcm.
I've had a couple of occasions when the service has been unavailable, but their customer service is the best I've encountered.
There is no problem transferring your internet from one machine to another - you just plug the usb modem in to any suitable machine, it automatically loads the necessary software, and connects - no long wires, filters, or other stuff.
For convenience, I'd highly recommend it.
Hope this is helpful.
'Hat.