My advice to many that are asking the large multi-GB HD (or Flash) question (on an A1200 or A600) for the first time is simple:
Get a 4GB CF or similar module to start, and partition into 2x 2GB FFS partitions.
This skims past the problems encountered when you go past the signed and unsigned 32-bit integer issues (which is what lurks at those boundaries mentioned). Once you get the above running, then delve into the issues with newer file systems (mentioned above) and newer OS/Support tools that can handle media in the areas above 4GB. You also have your backup on your original 4GB media.
