The clear practice cylinder I'm interested in:

The detailed description reads:
We have had great reviews of our Clear Practice Locks. They are great for learning and teaching locksmithing and lock manipulation. Each lock uses a SC1 keyway. These are available with both Spool pins and Standard pins.
Actual url: http://www.lockpicks.com/index.asp?Page ... ProdID=288
So basically just a couple questions:
-Do they really help in the learning process? (I mean, enough so that it's worth the $34)
-Is getting a clear cylinder better than just getting a regular practice cylinder? (Because chances are I'll only be able to afford one right now...)
I have really no experience with practice cylinders at all (I've just been practicing on random locks I bought) so I was wondering if the pins on this one are removable so I can adjust the level of difficulty?
Any help appreciated
