As a general user and new to the GL-inet product. I’d look into these
1.The track record support for their product lineup.
2.The outside support, OpenWrt / LEDE.
with these two it should tell you how long the router will officially / unofficially last.
And for the Brume / Slate comparison. I’d go for the Brume because
- It’s much more powerful especially for OpenVPN.
- Its storage is much bigger.
- It has a longer support.
… and for the popularity, this is less concern for me because as novice as I am it looks to me like the GL-inet positions the Brume for professional / intensive use, hence a reasonable good amount of work into the firmware can be expected and it should at least outweigh the popularity.