30 minutes? Most external USB3.0-HDDs can read or write 130 - 170 MB/s, that's 8 - 10 GB per minute.
So a 80 - 100 GB game can be copied in ten minutes, a 40 - 50 GB game in five minutes.
It takes 35 minutes to copy GTS (108 GB) atm. It's read plus write on the same drive, so from HDD to SSD it shouldn't be more than 20 minutes.
Theoretically it should be a lot faster yet HDDs hate tons of little files. Read and write speed drops to 1/10th when game files are a collection of small files.
On the right is my HDD inside my laptop (which is rated at 103 MB/s read / 97 MB/s write speed)
It depends on the game file structure.
Anyway doesn't matter if it's 5 or 30 minutes, not gonna wait when the whole point of SSD is, turn on and play in half a minute.