I've had a few Mifis, they're good kit (certainly MUCH better than the faff of installing dongle drivers on a PC).
Be aware though that most Mifis are SIM-locked and need unlocking before using a local SIM card (which would be the sensible thing to do when in a foreign country). The unlocking procedure isn't childs play however, so probably best to ensure it's done in the UK before you leave (when you don't have to shout and wave your hands around to communicate with non-English-speakers).
