I don't think there has been any definitive comparison for tethered performance between core i7 and core i5 Surface Pros. I would assume that i7 would be at least minimally better than i5 for processing in C1Pro8 and PS. For image preview, I doubt there will be much difference and I believe RAM is the bigger factor. Rumor mill is that the upcoming Surface Pro 4 may offer more than 8GB RAM.
I doubt the fan will have any significant impact on stability or vibration, but I think Paul Caldwell will be the best one to ask here. If the possibility really bothers you, you can simply separate the SP from the tripod equation and hold it, set the SP on the ground (on your bag) or place it in a tripod sling/holder. I know there are a few that don't use the clamping options,
but I don't think it is because of vibration fears.
I think Microsoft's battery estimates are generous, but I think around five hours is a pretty good range---it really depends on what features you have enabled and what you are doing. Be aware of battery management features, as well as the ability to change charging functions to the MFDB: no charge, slow trickle, trickle me more). I use the no charge option.
There are external battery options, but I think when you start going down this route, it really defeats the purpose of being mobile. That being said, the Vagabond Mini Lithium can be used as a charger. I assume that by now there are other small lithium battery packs that can be re-engineered to fit assuming the voltage matches. I recently purchased a small lithium pack for my truck (ok, didn't need it but it's really cool) that I can use to charge USB devices and it has enough power to jump start Don Libby's Ford Raptor. Cables included! Ok, I digress.
I've been busy, but am about to write another blog article on the evolution of the Surface Pro clamp options. I have yet one final new clamping option---and I think this one really is a winner!! Small, lightweight and huge improvement over the first generation Arkon, Wolf clamp, and hiking Pig clamp. Super happy with this new clamp and will have the article up shortly.
My original blog article has been updated to include shopping lists of items needed to tether with the Surface Pro, but future updates will be in separate articles, including the new clamping system.
https://kendoophotography.wordpress...s-and-leaf-credo-medium-format-digital-backs/
I'm looking forward to the new Surface Pro 4.
Ken