Yes, these do look very good. I have the Surface Pro 3, which I use with two external monitors. The one thing I don't like about the SP3 is that the 10.1" screen is too small for my preference, I think my eyes are going as I get older and it's just too small to have a comfortable resolution that can also show enough stuff. The Surface Book looked very good when I watched the presentation, the only thing I really want is a 15.6" screen one, then I'd look at getting one. I'm kind of hoping they will bring out this screen size.
In general Microsoft are making a lot of right moves at the moment, and the hardware is looking better than Apple's now. The Surface Book and the SP4 are offering more than equivalent Apple products if you asked me.
Rgds