So, in order to actually benchmark this i had to run the commands a few times each (for example, cat_file was run 142 times a second for 30seconds!)
In the time it took me to cat a file 4260 times i could have opened 4680 files!
I think i'm going to keep using cat to read in single files :D
Here are some more runs with 10MB and 100MB files. I tried to test 1000MB but i ran out of memory :D