As long as you test the stability of each overclock, and you're happy with the temperatures you're getting, then its all good.
I've reached 2.6 with my X2 3800, and will keep pushing it until it wont go any further, or the temperature produced by the voltage is simply too high for comfort (PWM temp currently at 55C at full load/37C at idle).
Omega, is my PWM temp too high? Voltage is at 1.425