Sorry you misunderstood me - I was thinking only of the esp8266 to be the wifi adapter. Not as an alternative to the STM.
As a replacement for the emonTx for energy monitoring and solar diversion I’m not interested in battery power. I would think most emonTxs in these situations have 2 wall warts on an outlet near the distribution board. It’s these systems that could benefit from the faster analog on the STM micros.
emonTH doesn’t need fast analog and can obviously be battery powered.
Simon