If you wish, you can install the stable OSMC then tell it to upgrade to the latest alpha release via updates
I’ve tried this a couple of times and it updated ok to KODI 18 but had various issues with videos stuttering or various issues with ‘some’ add-ons simply being unpredictable
Had to re-install OSMC to get back to KODI 17.6 and ALL video issues were fine, but under KODI 18 cause problems. I also use RetroPie installed via RetroSMC and this does have issues if you upgrade to KODI 18 ALPHA, under OSMC 17 things work great
My main reason to try out KODI 18 is the emulation that is now part of KODI 18, but could never get it to work as I thought it would. As it says though … it is an alpha release so WILL have issues that may cause problems later if things change
KODI 18 does work, and some things are much better but has issues. Considering its still in ALPHA release it is for the most part stable and does what it should, just needs a few things working out
If you want to try the KODI 18 update, you’ll need to follow these instruction. BUT once you have upgraded you CANNOT downgrade. If your not happy or isn’t stable enough for you, then you WILL have to reinstall from scratch to get back to OSMC KODI 17