Check out the latest ASUS T100, running Windows 8.1 and quadcore Intel BayTrail SOC. Only 2 GB RAM, that could be a bit problematic.
NOTICE : Do NOT know the performance of Cubase on this thing.
Have seen YT vids where games like FIFA14 run quite smoothly on this € 350 tablet, keyboard included.
Internal space is some 17 GB, windows of course takes up a great deal of the original 32 GB space, so microSD should be employed for more storage. It even comes with 2 USB ports.