Quote:
If you have already saved games or stored content on your Xbox 360 Elite system's 120GB hard drive or the Xbox 360 Special Edition 20GB hard drive, those games and that content will be erased during the content transfer.
-offical xbox site
although i think that means it overwrites when transferring ONTO the larger hdd, not that it deletes saved games while transferring across.
also said something about once it's been transferred to the larger hdd, the larger one can then long be be transferred to another hdd (smaller or larger).
so i'd suggest making sure the newer larger hdd is large enough.
try here to buy:
http://www.oztion.com.au/buy/auction.as ... &freepost=