Hm, the "twice as fast as MacBook Pro" quote made me believe they were using 28W laptop Skylake parts like
Apple does in its MacBook Pro:
For the most part, midrange and high-end computers that are 13-inches or smaller in size all have pretty much the same specs: 15W CPU from the Haswell-U or Broadwell-U product lines, midrange Intel integrated graphics, 4GB or 8GB of RAM. There are exceptions—lower-performance devices with Atom or Core M and the occasional high-performance boutique laptop—but most of the time a smallish laptop comes with lower specs relative to what you'd consider a "workstation."
The 13-inch Pro is relatively unique in that it uses the 28W versions of the Broadwell-U chips. They have the same ingredients as the 15W parts (two CPU cores, an integrated GPU with no eDRAM), but clock speeds are higher all around, and the larger thermal envelope means they can run at higher speeds for longer. The i5-5257U has a base clock speed of 2.7GHz and a Turbo Boost speed of 3.1GHz compared to 1.6GHz and 2.7GHz for the MacBook Air—not a big difference when both are boosting, but quite a bit of a difference when heat has throttled them both down to their base frequencies.
That's not the case, as
the SurfaceBook uses a 15W ULV Core i5 6200U, which makes sense because most of its internals are in the "lid" portion.
Microsoft have probably cherry-picked a graphics benchmark. It's also important to note that the MacBook Pro hasn't had its Skylake refresh yet, either, so it's probably not the most flattering comparison, though that Maxwell GPU in the high end model will indeed outperform Skylake Iris, and of course outperforms Broadwell Iris in the current MacBook Pro.
I have a Surface Pro 2, and I'm looking forward to replacing it with something like a retina MacBook Pro or a SurfaceBook, but I'll probably lean towards the former if the latter has throttling issues.
Was pretty disappointed with Microsoft's presentation in a way. There was a lot of empty hyperbole and misleading figures (the SurfaceBook's quoted weight statistic is another one), which are easy quotes for press articles, and something about it all doesn't sit right with me.