Having played with all of this before I have some opinions on a few of these things. I have half a dozen of those TP-Link routers in a drawer, they're fun to p

Having played with all of this before I have some opinions on a few of these things. I have half a dozen of those TP-Link routers in a drawer, they're fun to play with and ok for on the go. For traveling I'd stick with one off those over a Raspberry Pi, or better yet, for a nice little upgrade I'd go with one of the GL.INet routers, I have a few of those too and they all support OpenWRT/LEDE. They come with it out of the box (albeit with their GUI on top). RPi is sensitive to power fluctuations and note great for travelling because pulling the plug a couple of times will likely destroy your micro SD. If you were to use one for travel I'd suggest mounting your microSD read-only for maximum safety. I've been through a dozen or so cards in a static Pi before I switched to ramdisks and read-only root. Currently I only use my mobile as a hotspot because it's inconvenient and extra cost to have additional SIM/data when my mobile contract offers plenty.