I have four Windows portables. One of my main uses is taking something to our camp on the weekends so I can answer questions if my students have them. For most things, one of my iPad Pros work fine (love the Apple Smart Keyboard) but if I need to run a program, I need a Windows computer.
My 13" Toshiba Portege is too big, my Surface Pro 3 is too big, my Surface 3 is too big, and my Dell Venue 8 Pro is too small. That 10" screen is my sweet spot for portability.
Some people don't think three quarters of an inch or an inch make a difference, but some of us do. I'm happen to be one of the latter. I also don't use a mouse with any device that has a trackpad so I only need the Go and the keyboard. I'm thinking that the weight and size will be very comparable to my iPP 9.7 and iPP 10.5 (both with silicone back covers and ASKs).