20 minutes is close to the average to install all games on the 360. It being under 4 gb's doesn't matter.
Uh, yes it does matter. The smaller the size of the file the less time it takes to install. This applies to any type of installation. :|
Actually no, it depends on the sizes of all the files INSIDE the install file, that's not just one big file you know.
If there's a crapload of smaller files, it's going to take longer because write speed for lots of smaller files is SLOWER, not faster. It's actually faster to write large files than it is smaller files.
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