The timings given for each node are measured on the machine you are running the Substance Editor on, probably using the DX9 engine if you are on a PC and have not changed the default settings. It is quite likely that the actual performance on a given mobile target will be slower as your computer's GPU is probably much more powerful than any existing mobile's CPU.
However, the relative speed of each node should be similar, so you can still use those timings as an indication of where optimisations are needed.
It is possible that you will get performances closer (i.e. slower) to what you will observe on your mobile target in Designer if you switch to the CPU (SSE2) engine (in Tools->Switch Engine...).