I must disagree. I know exactly how much RAM and CPU time my tasks take. On my Ubuntu machine a build can easily take 20gb of RAM and saturate the CPU for half

I must disagree. I know exactly how much RAM and CPU time my tasks take. On my Ubuntu machine a build can easily take 20gb of RAM and saturate the CPU for half an hour. If I want to test my software on windows, that means a VM taking another chunk of RAM. I have seen my system consume almost all of 64gb. I have seen the difference between each generation of i7 and my build times keep going down. For about 5 million LOCs of C/C++ the first takes about half an hour and the 6 gen takes about 3 minutes. For systems developers this makes the Mac Book Pro a poor choice. But other laptops are almost as good as Desktops until we start needing things like CUDA (or more than 8 cores).