Re: Going back to Thinkpad
same general memory and processor options,
Memory, yes, but not processor. The "New Surface Pro (5)" model used 7th-generation CPUs, while the "Surface Pro 6" uses 8th generation parts. That's a significant improvement in power consumption .. or performance, depending on the system designer's priorities.
Battery life is quoted the same, 13.5h, but the "battery life" test that everyone uses really only measures display and video decoding, so performance on more representative workloads could be very different