I haven't tried the new Bitmain firmware because of all the issues listed herein.

I switched over to the Antminer S5 firmware image provided by nicehash available here: https://www.nicehash.com/?p=software

You will note they use CGMiner 4.9.0. They state on their website: "You can download pre-compiled binaries for AntMiners with updated cgminer and extranonoce.subscribe patch and replace stock AntMiner cgminer binary or firmware to benefit from newer cgminer and extranonce.subscribe for better efficiency".

I agree with their statement as I experienced increased speed and a lot less rejected shares using the extranonoce subscribe patch.