Thank you for those that are testing the MT2500. I want this router but have been waiting for it to be included in a stable OpenWrt release.
Regarding rc5 working fine but rc4 and previous releases having problems, I didn't notice any changes in the changelog that would explain the improvement.
I wonder if the problems people have been seeing here are related to the many cases of bricked/dead MT2500s reported in the GL-iNet forum, which GL-iNet think might be a hardware problem (see link below).