FWIW, I get different results depending on which (rooted) ROM is installed.
With (rooted) stock 4.2.1 (JOP40D), I use StickMount and everything seems to go fine, with the mount at /sdcard/media/usbStorage/sda1.
When I tried using StickMount on a recent CM10.1 nightly, the mount would happen, but the permissions were screwy and the results I got with root-privileged file explorers would vary depending on whether I navigated to the mount via /sdcard/... or /data/media.
Turned out that CM10.1 performs the mount itself - and StickMount was actually interfering with the correct operation of the auto mounting performed by CM10.1; once I uninstalled StickMount, everything was fine. It does put the mount at a different spot, though. I can't remember the location at the moment. You can find it easily enough by typing "mount" in a terminal emulator.
Hope that helps.
eu1
PS What ROM/kernel are you using?