The PRS John Mayer Signature guitar has been based on Paul reed Smith’s and John's favourite elements from vintage instruments that they own which are dated between 1963 and 1964 – I’m sure you can guess which style of guitar!
However there have been some specific design improvements that make playing the guitar far more enjoyable for players of all levels. The lush John Mayer sound is achieved thanks to the 635JM single coil pickups. These pickups offer you a vintage-style sound but also feature a higher signal-to-noise ratio than traditional single coil. This results in the 635JM's providing less hum and noise than you'd usually find in single coil pickups. These pickups also maintain a musical high-end without any of the usual "ice-picky" sound that can sometimes be found in vintage style pickups.
As John Mayer famously quoted about these guitars, the string tension has also been addressed, providing a responsive playing experience thanks to expert tweaking of the distance between the bridge and tuning pegs.