It is Intel, and ASUS is one of the best for Intel. Abit tried to make overclocking easy - and they succeded in making that, as you can't overclock well with them.
Anyway stick with the ASUS with Intels.
Stock hs for Intels are meant to be one of the best avaliable air cooled coolers.
For adding the AS5 I did the same as turtile said, but you only need a blob of artic silver 5 the size of a grain of rice to cover the heatsink nicely.
Use isopropyl or anything above 90% alcohol to clean the heatsink and CPU fully.
Use the cloth that you clean sun glasses with as well to clean the CPU and heatsink - anything lint free.
Edit: - I don't want to scare you, but when you take the heatsink off, the CPU may be attatched to it, due to the thermal pad. To try and prevent this, put your PC under alot of stress, and make sure it gets hot, so it will warm up the thermal pad so the heatsink will come off nicely, but it may still be stuck on the end of the heatsink, so when removing it, make sure that you lift upwards, and not at an angle.
Cisco CCNA, Comptia A+, 1/3 through CCNP