I'm really surprised how well loved the Surface Pro 3 is in this thread. It's almost making me a bit suspicious. To start with, I'm not putting anybody down who owns one and enjoys it, more power to you. I just have to add my opinion with my own experience in mind.
I decided to expand on my education and chose the Surface Pro 3 as my choice because I could write on the screen which would help memorize terms/ideas. While the writing does help with memory and I use my Pro 3 extensively, I find it to be too buggy and unreliable to be considered a good experience. Just to give some examples over the past couple of days, if you are in an application and move your finger to the right, you are supposed to get an expose-like view of all of the opened apps. I was doing that repeatedly because i was switching between Excel, Word, and Edge and then the screen froze in the multitask view. Then it'd start to respond for a bit to allow me to maximize an app and then it'd freeze on that app. Basically I had to restart the OS.
Also, when I use the touch interface in a document I'll scroll through it but because I move my finger too far to the right, it will go into the multitask (expose-like) view. So then I'll have to select the app again to get back into it. Frequently, if it's a webpage I'm viewing, it will be on the top of the page and I'll have to scroll back down to the correct location of the webpage again. The stylus that comes with it is very responsive but when I write in Onenote I like to wrest my wrist on the screen and that will frequently cause me to move to a different location in Onenote and I'll need to scroll back to where I was. Frankly, I have many more examples but I don't want to write a freakin book here.
You guys are complaining about IOS being a "Phone OS" and while that has some validity, you need to keep in mind that IOS was designed to be a touch interface, and too that end it's an excellent device. With IOS 9 expected to be more rock solid than IOS 8, you have an OS with tons of productivity potential. Apple is moving in the right direction by adding keyboard shortcuts. I just think they need to go further and develop cursor support into the OS for a mouse and also keyboard arrow keys. See, Microsoft has a good idea with their touch interface, and switching back to a desktop OS when the keyboard is plugged in, but neither the touch interface or the desktop interface is refined enough or reliable enough. And what Apple should be able to realize is that there isn't a need for two interfaces. You add in robust keyboard short cuts, and cursor support, and basic file system support and you have yourself the ultimate hybrid OS.
Let's take a look at Apple's advantages over Microsoft in the quest for hybrids. I bet you the combination of IOS 9 and the A9X processor with allow for over 15 hours of battery life easy. Because I'm a relatively light user with my Surface, I can get around 6 to 7 hours. IOS doesn't crash every often at all, as you've seen with Windows 10 it's very glitchy. We'll have to see how Apple's wrist cancellation is, but I bet it's way better than Microsoft's. Also, the problem with the Microsoft stylus is the two buttons built in. They are admittedly useful, but I press them by accident which causes me to accidentally erase what I just wrote. Kudos to Apple for staying away from adding buttons to their pencil.
I think, from what I've read, folks are giving Microsoft too much credit, and underestimating the potential of IOS 9.