Thanks for getting back to me.
Have dowmloaded GSAM and it tells me that 96.7% of my battery drain is from the Android System. There are 237 wakelocks in this!
Compare that with the amount of Wakelocks in my Launcher (GO) at 1, it looks a little bit suspect!
I too am on Google Play 4.3.11. I've force Stopped Google Play Services and have now rolled back to Play store version 4.0.25
Will let you know how I get on.