There are a few simple reason as to why windows tablets are much much more suited for making music then android or Apple tablets..

1) all professional music software is written for windows (or mac osx, but that does not support touchscreens)
2) tablets do only allow one active app at a time (front) apps in the background are on hold by default. But windows pro allows full multi threading and multitasking, which results on windows allowing the software to interact with eachother.. Or even sharing the screen.
3) windows tablets natively support all the needed interfaces.
4) windows tablets come in larger sizes.

If you want to use your tablet for professional music making, windows 8.1 is currently the way to go..

So far after extensively testing both Ipad and windows tablets (not the rt tablets, because they suffer the same problems as the apple and android tablets) i think choosing anything different then windows 8.1 pro gives you nothing more but an expensive toy ( with music apps) , a good music reader and an MP3 player... While windows gives you all the professional options.
Please feel free to discuss..