Thermal compounds are always expensive, so unless you put mayo are between heatsink and CPU, will have to invest in good dough. Unless you change it every year rarely reach the end of the tube, so be careful not to take too much. In terms of performance, I have never seen too many differences between the thermal compounds, it is mainly on longevity of the product to look out. In the case of the MX-2 artic, I can confirm that it is resistant and does not need to change after about a year. Although it is advisable to regularly change (seriously, made it), one can forget to do it once, the MX-2 does not lose its performance.
