Three UK is marketing its DC-HSDPA and upcoming LTE networks under the the consumer-friendly name "Ultrafast," and today sees the launch of a new Galaxy S3 variant intended to take advantage of this network. Three's Ultrafast Galaxy S3 is identical to the vanilla 3G version, except it'll run at full-speed DC-HSDPA, as opposed to maxing out at plain old HSPA+. Basically, that means you get up to double the download bandwidth wherever there's support for the faster network speeds. (If you want to get even more basic, it means your 3G will be twice as fast.)
It's not explicitly confirmed in today's press release, but it's likely that Three's Ultrafast S3 is actually the Galaxy S3 LTE (GT-i9305) — that's the international LTE version that also includes DC-HSDPA support thanks to its Qualcomm radio chip. We've reached out to Three to clarify whether its "Ultrafast" model will indeed support the upcoming LTE service, and we'll update this post with any info they provide.
In any case, you can expect to pay £449.99 to buy the Ultrafast S3 on PAYG, or between £34 and £36 per month with a £29 up-front fee on Three's 24-month contracts. The phone launches online and in Three stores next Tuesday, Feb. 12.