Have you ever tried to create *content* and effectively distribute it on an (unjailbroken) iPad? It is an exercise in futility and frustration. I have both (okay, not a surface, but Sony Win8.1 tablet), and I only use the iPad for surfing, watching the occasional TV show in bed, and as a big GPS in the car. OTOH, I use the Sony to edit CAD drawings, type up reports and send them to clients, mark up architectural prints (pixel accurate pen FTW*), compose music, transcode and distribute audio files...pretty much everything I can do sitting at my desk. The iPad is a toy - granted, a toy that has some utility - but it's just a toy.
*I've tried about 4 different pens on the iPad, from $10 eraser points to $100 bluetooth jobs. None of it comes close to "writing". Even with the "same" program (Bluebeam, which has an iOS and W8 version) it's just painfully slow and inaccurate on the iPad.