Working well on mamba and rango for me. Quite a few people use the updated one from the forum thread, but that is actually ahead of what is currently in master. I would not anticipate any breakage issues with cherry-picking the current one, but..., should add I am only running master.
I have been using 18.06.0 (including all prior pre-release and release candidates) and have always updated to the latest mwlwifi drivers thanks to @eduperez and his pre-compiled (latest and greatest) mwlwifi drivers/firmware (https://github.com/eduperez/mwlwifi_LEDE). It has been a rock solid experience in recent months. In my case, it is the WRT3200ACM. My network is a mix of devices (ultrabooks, iPads, iPhones, gaming devices, Netflix, etc. The wife and kids have not complained at all in the last 6-8 months or more, so that generally is a good thing.
I would vote in favor of backport based on stability.
Hi I am running:
OpenWrt SNAPSHOT r7773-1c4a255 / LuCI Master (git-18.220.31345-7609919)
I am not shure what driver this build has, but it's working fine.
Pleas can you see if the driver in master is the latest?
I am currently repackaging updated drivers from mwlwifi's repo, and publishing them at the link mentioned by @WildByDesign. In practice, the people who download and install my packages are running the latest version from mwlwifi.
The general consensus, and my personal experience, is that drivers have been improving with time. However, latest commits have been centered about preparing the path for MU-MIMO (which is still unsupported), adding support for 8W8997 (which is not used by any device supported by OpenWrt, AFAIK) and some cosmetic fixes; I do not think there is anything really interesting after version 10.3.8.0-20180615.
As I understood @eduperez and the others there are no known problems in version 10.3.8.0-20180615 (used in OpenWrt master) compared to version 10.3.4.0-20180330 (used in OpenWrt 18.06.0), so an update of this version in OpenWrt 18.06.12 would be ok.
An update to version 10.3.8.0-20180716 would not change much.