I have mobile broadband via my Nokia 85 on 3. I think that's 3G, but not taken too much notice as, IMO it's abysmal so I've not tried it more than a dozen times.
I also have mobile Broadband for a lappy on 3. Now this runs HDSPA, which is supposedly twice as fast as anything else on the market.
It's on a par with an old 56k modem and constantly drops connection, even in heavily populated areas, when not moving around, although, to be fair it occasionally goes a bit faster.
It's useful if you have no other option, but jeez it's tedious.
And not cheap either at £15 for 3Gb and £100 for the modem.
Faddy load of rubbish?
Totally, at least for the near future, IMO.
I wouldn't bother if you can do without it