The Sony a7R is a remarkable camera, and I've been fortunate enough to get one. I had a heavy, but excellent, Canon DSLR system for something more portable. I visited the History Live event back in 2011, and by the end of the day I was aching. Returning to the event again in 2013, I was only a couple of hours in to the day and had to abandon my 400mm lens back at the car; finishing the day with my trusty 70-200mm f4, and back ache to remember. That was when the seed was sown that I was getting too old for the heavy equipment. The final straw was walking along the coastal path north of Bamburgh, it was a chore to haul the kit to get the photos. Enough was enough.
On returning home, I ordered the Sony.