ENTHUSIASTS! 
HariA (I don't think he frequents this forum) has done a comprehensive writeup on the R1200GS DOHC......well actually a whole series of articles (listed below)!
See here:
BMW R1200GS 2010 onwards / R1200 DOHC
BMW R1200GS DOHC
Descriptions, specifications, technical information (e.g. ESA and DDC) and comparisons with previous models.
ESA (Electronic Suspension Adjustment)
An overview of what BMW ESA is, how it works, problems and aftermarket suppliers
ESA Rider Guide
A guide on how to use and get the most from BMW ESA
DDC Dynamic Damping Control
An overview of BMW Dynamic Damping Control (DDC)
Öhlins Electronic Adjustable Shock Absorber System
An overview of Öhlins' replacement suspension kit for any R1200GS already fitted with BMW ESA
R1200GS DOHC Competition
Comparisons of BMW's R1200GS DOHC with its main competitors and the author's personal experiences:
Hari's R1200GS DOHC
A brief intro to Hari's biking history (that goes back a few years!
followed by Hari's personal experiences of 2 years riding his own BMW R1200GS DOHC
plus:
Aeroflow screen with Saeng edging (not pretty but very effective)
R1200GS conversion to F800GS footrests (wider and more supportive than stock)

HariA (I don't think he frequents this forum) has done a comprehensive writeup on the R1200GS DOHC......well actually a whole series of articles (listed below)!
See here:
BMW R1200GS 2010 onwards / R1200 DOHC
BMW R1200GS DOHC
Descriptions, specifications, technical information (e.g. ESA and DDC) and comparisons with previous models.
ESA (Electronic Suspension Adjustment)
An overview of what BMW ESA is, how it works, problems and aftermarket suppliers
ESA Rider Guide
A guide on how to use and get the most from BMW ESA
DDC Dynamic Damping Control
An overview of BMW Dynamic Damping Control (DDC)
Öhlins Electronic Adjustable Shock Absorber System
An overview of Öhlins' replacement suspension kit for any R1200GS already fitted with BMW ESA
R1200GS DOHC Competition
Comparisons of BMW's R1200GS DOHC with its main competitors and the author's personal experiences:
Hari's R1200GS DOHC
A brief intro to Hari's biking history (that goes back a few years!
plus:
Aeroflow screen with Saeng edging (not pretty but very effective)
R1200GS conversion to F800GS footrests (wider and more supportive than stock)

