I agree that the website doesn't explain the concept well. I have the xtreme xtension and when I saw the muscle chuck, I thought something was "missing". Yeah...this thing doesn't go in like a router bit. This muscle chuck replaces the collet nut and collet! I love the idea and hope it works.
I'm struggling with standard two wrench bit changes (and as a result avoid using my router, even though I love the result). So use of an allen wrench...one tool, to change the bit is very appealing to me. I finally got that xtreme thing working but I can't lower the bit below the table. Now that I use the router table as an "extension" of the table saw table, not being able to lower the bit is now a huge problem, thus, why I started searching for a shorter alternative.
I find that the "basic" package at $106 is ridiculous. I found the same wrench for $3 (or a premium one for $7) and an insert for the 1/4" bits for $13 (though, I may be able to reuse the one that came with the xtreme) and then the chuck for $70. Now at closer to $90, I'm happier. There's no need to over charge for a collet reducing thingie and a wrench!!!