I managed to give my friends Vodafone Mobile Broadband connection a try recently while attempting to figure out which was the best operator to choose for my remote working. Speed varied a lot between 700Kbps and 1.6Mbps but I was quite pleased with this, though for whatever reason a number of websites had loading problems, probably issues with me moving between indoor and outdoor locations.
Vodafone, like Three (3), is fairly well priced, though I'd probably rather have Three's 5GB for the same price as Vodafone's 3GB and take the lower speed. You don't get much in the way of services with Mobile Broadband, it's just a raw connection and since nobody does any different then I can't really rate it down.
Pretty good so far, can't complain and apparently customer support is reasonable but occasionally a bit slow according to the owner.