I agree that you should test on more limited hardware. But on the other hand, I use my high end development machine as the benchmark for how fast it will go wit

I agree that you should test on more limited hardware. But on the other hand, I use my high end development machine as the benchmark for how fast it will go with a production worthy machine (unless one is willing to throw really insane amounts of money around). If the customer asks "How long does it take to import 10k documents?" I can give them two data points, the VM running on a slow DSL connection over VPN on an older server, and a VM running locally on a i7 with more RAM and an SSD. Of course, the requirements change if you develop desktop applications vs. server applications: if you plan to deliver software to government accountants running hardware that is at least 5 years out of date, you better go and get yourself a matching setup - "It would be faster if your Boss bought you a faster machine" is not helpful.