Does anyone know of one or used a chain device for a 30t ring up front?

I just used an MRP 1x guide, the seat tube mounted version. Just mount it lower than usual and BOOOOOOM it works for a 30t chainring – successfully i might add for a week in les 2alpes with zero dropped chains

I just use a narrow/wide ring. No need for a chain guide.

I use an MRP AMG v1 on mine.

ive used mrp and e13 1x guides with 30t

e13 works slightly better

and with a narrow/wide i still need one on my full suss bike, especially if racing, even sponsored ews pros all seem to run top guides with their 1x setups

New OneUp one looks god, or that Freesolo one

That freesolo one looks good, handy that you may get away without having to remove cranks to fit! Out of stock though. I ended up ordering the Gamut trail sxc. See how i go with that…

DMR viral (about £50 online) goes down to 28t if you need something cheap which works and has upper and lower guide retention.
(if you’re really clumsy the lower guide plate can bend in an impact (being steel it’s usually easily enough bent back though)