OK, even 2 GB RAM is enough (one of my PC's is also running PIanoteq with only 2 GB of RAM), but again: "not a lot". When you want to run some other VSTi's you quickly see the limits. But the CPU also plays its role, and the OS, and... everything else !
And again: just look at other comparable machines, branded under the Acer, Asus or Lenovo umbrella for example, there is plenty of (better IMHO) choice in this price range. Two years ago I bought a Toshiba "convertible" (13" touch screen, 360° foldable) for under 500 €. Except for the screen resolution (and the weight), it beats or equals the Surface on all aspects.