Heat sink on the Ivy i5357OK - use as is or scrape and use Therm Compound?
There is nothing wrong with the thermal paste that comes on the stock heatsink. I wouldn't worry about replacing the thermal paste unless you take off the heatsink or start to have temperature problems.
If you want to do heavy OCing, replacing the CPU heatspreader's paste with a better quality can drop the temperature by a few Celsius depending on what cooling system you have installed.