Which tablet or laptop?

Since now I have the NUC and ROCK, would like to get either a laptop or tablet to use as “remote”… would this one work?

Microsoft Surface 3 LC5-00015 Intel Atom x7-Z8700 (1.60 GHz) 4 GB Memory 64 GB SSD 10.8" Touchscreen 1920 x 1280 Tablet Windows 10 Pro 64-Bit

or do I need to get one with an Intel i3 processor?

Your surface 3 is listed as an appropriate device. See here https://kb.roonlabs.com/FAQ:_What_are_the_minimum_requirements%3F

good, thanks!