I have decided, yet again LOL, to hold on to my SP4 for now. I had narrowed it down to either keeping the SP4 for now, or exchanging it for the rMB. I ultimately went with the latter as I prefer it as an overall package. When I found out that the battery life between the two is somewhat negligent, with the rMB maybe getting an hour improvement, it kind of sealed it for me. I have until Jan 31 to return the SP4. It makes more sense to ride it out and see if rumors get stronger about v2 of the rMB in the new year. If so, I can easily return the SP4 and wait on the 2016 rMB or maybe rMBA. As of today, I just prefer the SP4 as a single, do it all device to anything Apple offers.
Also, for those of you that own a SP4, I did a reset of my SP4 which included a reinstall of W10 and all of the latest patches. I've also changed the settings so that the system goes into hibernation instead of sleep. Battery life has improved since. We'll see if it continues.