i dont think that every one should try to change the multiplier, specially if they cant afford burning it.
overclocking is just for performance freeks, not a real way to work with you mechine.
i for example overclock only to work out some benches and then i set it right back, warenty is important to me as i am in the army right now and cant work.
asuming you have anough cash to buy a new part then go for it.(especially if it need fisical modifications to do the OC)
*(k)eep (I)t (S)imple (S)tupid*