I did some Google Fu on the Surface Pro 3. I don't know a lot about the CPUs other than that they seem to be mobile versions of the Intel Core i3, i5, and i7. The i5 versions (depending on built-in storage) seem to be priced from $750US to just under $1000US, while the i7 versions seem to be priced from $1250US and up.
There's plenty of system RAM (up to 4GB), but the disturbing thing is that the video subsection is integrated (Intel HD4000 series). I've not been able to find out how much dedicated VRAM is available, but on most desktops and laptops using Intel HD4000 series video chipsets, they tend to come with at least 128MB of VRAM. That *should* be enough to display RoM's video, probably with reduced settings.
And remember that the Surface is essetially wi-fi only (wireless connection), with all the attendant problems that can cause. There's no external port for a wired 'net connection, unless you want to tie up the USB port with an Ethernet adapter.
While some people have had issues running the game under Windows 8/8.1, usually touchpad issues, it should work.
I would strongly suggest that, before plunking down a megabuck or more for one of these tablets, you see if you can find someone, or a friendly-enough store clerk, who would be willing to download and install RoM on their (or a store) Surface Pro 3 and see if it will run.
In other words, Caveat Emptor.