Following a discussion with someone else on this forum who insisted that all S4s with stock ROMs lag, I decided to try a Google Play Edition ROM on my S4 to see whether I could tell the difference in terms of speed and responsiveness but I couldn't. My S4 has always felt snappy and lag free and it felt just as snappy (no more, no less) running the Google Play Edition ROM so I reverted to my nandroid backup of the stock Samsung ROM.
However, this got me thinking about other ROMs and I wondered what people's experiences had been like with Cyanogenmod, which I have used on my Xoom tablet. Are there any real advantages to Cyanogenmod over the stock Samsung ROM? If so, what are they?