Water-cooling was inevitable, and hinted at in interviews by BMW brass a year or two ago. Porsche had the same dilemna in the 90s with the 911. In order to meet emissions and deliver the power that we all demand (whether we can use it or not), they had to go down this path.
I love the air/oil-cooled bikes, and they will always be my favorite, but my 1200GSA is a very sophisticated piece of kit that has a lot of electronic wizardry. It is not simplicity that drives the fondness for air/oil-cooled bikes anymore, it is a sentimental attachment.
When I need simple, I jump on my R50/2, and if anyone has an R100GS PD for sale, drop me a line