Earlier quoted context omitted.
You'll stay with the tech you locked yourself in. I work in one of several buildings and macs there are just to let others know that you are a manager and you can get away with anything you want. Beside that everything is a MS pc and will stay that way until the business die. Getting everyone into the system is infinitively expensive, so is getting everyone out of it.
I work in a large 5000+ software company and were honestly about 30-40% macs. An MBPr is a good investment - I figure my 3yo machine will easily retain about 35-50% of its value if resold.
I suppose the enjoyment I have received from using it could be considered dividends of sorts, and so I could see calling it an investment from that perspective. But not financially.