Personally I think that if you can run either Prime95 or Intel Burn Test for some time (lets say 4 hours) then you're good to go.
I also think that no matter what you should always expect a BSOD even with a stock system. Machines are not perfect and neither are the people who make them
Prime 95 for a couple of hours (I'v heard people recommend 12) for the CPU.
Furmark burn in test, 3D mark 11 and intensive gaming (Crysis 2 or something) for the GPU.
Run Memtest and to check if theres any problems with your RAM.
If all comes clean than you should have stable build.