RT-N56U Custom Firmware

Hello all, I have read around a bit and according to the information I have gotten the custom firmware from https://code.google.com/p/rt-n56u/ seem to be better, but as I have no previous experience with this I am left with some questions that I dont seem to be able to find using google.

How do I prepare the router:
Read that I should reset it to factory then just upload the custom firmware is this correct?

If I want to return to default Asus Firmware:
Read that I could hard reset it by turning it off and then hold down the reset button while it turns on is this correct?

Reason for this is because I want to increase performance by being able to turn off as much as possible that I don't use which would decrease heat and lower heat would in return give better performance, I have also seen people open it up and added heatsinks to the chips on the back. Is there anyone that have either tried this custom firmware or added heatsinks that have any experience and pointers they could give me?

According to the link you should first back up your wireless settings with the .cfg file, this can be done from the router's set up page where it says firmware update etc.

Yes you just upload the new firmware from the routers firmware page.

I'm not so sure that just a reset will restore the old firmware, usually you need to upload the old firmware but your router might be different in this respect.

I'm not so sure that turning off stuff on the router will increase performance although using the 802.11N Only settings along with channel bonding will allow for the best possible wireless connection speeds.

That is the part I have trouble with also, the page I read talked about just a hard reset and then upload the firmware from asus but I am not sure and me and google are not best friends so I did not find much info on that part. I am only using the wireless for the phones and Sonos, computers are using wire as I live right next to a highly trafficated road and like 10 other routers so the wireless on the computers pretty much shut down as I could not game with all the inference, I could at first but each day went worse as more and more routers showed up