Actually...you can't really consider an overclock "true" until you are stable. Stability is a vague term, but most consider it Orthos/Prime stable for at least 8 hours. You may run fine under certain circumstances, but then have unexpected problems (random reboots and stuff).I don't believe one has to be Orthos/Prime95 "stable" to be classified as such. Stable to me is my computer doing what I need it to without crashing. It doesn't have to handle an extremely CPU intense program.
For example, my Trans Am can go 160MPH. Do I ever go that fast? No. Is that more than enough for me? Yes. Is it enough for NASCAR? Definitely not. But it needs to be able to go 70-80mph with no problems and maybe 120-160mph sometimes for fun. I don't need 200+mph.