I would use ModMii rather than installing the latest firmware officially. I used it on mine a month ago to move to the latest 4.3E firmware:
http://gbatemp.net/topic/207126-modmii-for-windows/
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What are the advantages of a modded wii? I've got the SD card standing by, but I need convincing to actually do it. Are there risks of bricking, as in early PSP modding?
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I'm sure there are always risks, I've not heard of people bricking it.
Advantages I found were the ability to run homebrew, which for some means emulators, and for me specifically ScummVM. And to run games off a USB drive, something I find very handy. Instead of swapping DVDs all the time, and lugging a big box with my Wii and games round to friends, I can leave all the DVDs at home and just bring a small external hard drive.
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