i know this has been brought up many times but i must post again for more new people to find in searches...
I bought 05 rex bout month and half ago just broke it in and had the same problem that 90% of new Subaru owners get ( compared to other manuals you have driven or even if this is your first manual you feel the clutch engages too high) By high it is meant that while releasing the clutch it doesnt "grab" untill it is almost fully out right when you feel the spring forcing back at you and your leg is bent very uncomfortably which you feel is making you bog/take longer at lights. So i read and read about how the engage point cannot be adjusted due to the hydraulic clutch untill i found that you can adjust the rod the clutch pedal is connected to that goes into the firewall. This will NOT adjust the way the clutch engages but will make the clutch pedal itself move lower (toward carpet) if you notice the pedal itself stock is about 1/4-1/2" higher than the brake pedal this is the whole problem if you adjust it to even with the brake pedal or slightly lower than, your problems will go away, the clutch will feel so much more "soft" (less push back at you), easier take off, smoother shifting, and less clutch travel.
So.. your yelling how do i do this... okay lay under your dash look above the gas pedal, push in the clutch, you will see the rod going through the firewall move. There is lock nut there loosen it, than take off the bronze retainer clip which will let you remove the pin. After doing this the silver "U" joint that the pin was going through can now be turned on the threads of the rod. Turn it about 1-2 turns where it moves lower on the threads. Lightly push the clutch in to line the holes up, put pin back in insert clip and tighten the lock nut and give it a try. Hope this helps you out cause it did me. Also important do not over adjust (no more than 2 turns) as it will end up hurting some things.