Here are the two different products you are referencing:
Panoptix LiveScopeô System
GLS 10 Black Box
Panoptix LiveScope LVS32 Transducer
Beamwidth: 20į x 135į
PART NUMBER 010-01864-00
Panoptix LiveScopeô LVS12 Transducer
Front to back: Two 30-degree sectors
Side-to-side: 20 degrees
PART NUMBER 010-02143-00
As you can see, it is true, one is cheaper and does not require the black box. However, you sacrifice a huge chunk of your viewing angle. You can only see down OR forward with the lvs12, whereas with the lvs32 you can see down, forward, and even a little behind you at the same time.
I am selling mine soon to get a matching Humminbird to link to my console, but if you are in SA I have the live scope system and you are welcome to check it out before you make a purchase.