I5 2500K Overclocking advice (For Noob)

*'COOLERMASTER 612S', sorry.

You won't know until you try and OC it. All chips are different.

I realize that but i was wondering whether the low voltage at stock frequency could be an indicator of a good oc'er. ?

Not that I know of. You know at stock frequencies it uses less then normal. It might stay true at OC frequencies or it might not. Depends on how "leaky" the chip is.

I have the same processor and use cpu-z as well, but people have told me that it is inaccurate in reading the precise voltages. However, it does get you a good idea on the rough estimate on what the voltage is running at. Every chip is different with overclocking. You cant just run in and take someones settings and input, and expect it to just be stable. With prime95, dont just run the small fft's, when or if you feel like that you have a reached a good clock and voltage, run the blend test for around 10-12 hrs. Everyone has a different opinion on how long to run these tests, so just research and come up with a conclusion on your own.
It is a low voltage, especially when the voltage stock is around 1.355 (If I remember correctly). However, I dont believe that is entirely accurate. If you have the cstates, eist functions on auto, it will fluctuate your voltage automatically during times of load and idle. So that may have something to do with it. During testing and overclocking, in my research people have said to disable these functions, causing the cpu to run at the full voltage set in the vcore for testing. After you have achieved a stable overclock, you can either turn these back on, or set an offset (more advised than returning back to auto) to regulate the load/idle voltages.