So I tried to extract the PAKs for SFV, and the resulting install was about 12 GB larger (about 32 GB uncompressed vs 20 GB compressed). So it is understandable why Capcom chose to compress these files, even if it leads to longer load times.
To unscientifically test loading times, I set Steam to offline mode and disabled my LAN connection. I then started the game, and entered training mode twice by placing the cursor on the Training Mode menu item on the main menu, and then starting the timer and mashing 'B' at the same time. My favorite stage was set to Bustling Side Street, and I had Balrog as my character. I repeated this twice and used the second time, which means that files should be cached in memory*. The second time for packed files was just above 10 seconds, and the second time for unpacked files was just below 10 seconds, so probably no real difference. On my system at least (which has both fast CPUs and a fast SSD), there does not appear to be any benefit from unpacking files when playing longer sessions (where files will be cached), and I have gone back to packed since that makes updating easier.
However, I did notice a real difference between online and offline, evident by a longer black screen with the spinning icon. The second load of an online, unpacked SFV run (as above) took about 16.5 seconds, more than 50% longer than the offline runs.
All of these runs included TOOLASSISTED's mod.
* On my system that should be the common case, since I have enough spare RAM for Windows to cache the entire game in memory.
