I want to repeat that I cannot recommend any of the Surface Books.
I got an original Surface Book and it was extremely unreliable. Over time the reliability of the software and firmware improved, but the hardware deteriorated much faster than my other notebooks: USB ports stopped working, keycaps broke, the unit picked up scratches much easier than my other notebooks and looks worse, the battery is practically useless now (and cannot be replaced), etc. I still have it and use it, but I cannot recommend it.
I think Microsoft just doesnt have the long experience in notebook manufacturing that the mainstream producers have, and the product suffers as a result.
For the money, you're much better off buying a high-end notebook from one of the mainstream producers who have been making notebooks for 20+ years and already have the best practices and experience to avoid surprises.