What is the difference between Superclock 1 & 2

I am getting a Modified Sony SCD 777ES Sacd Player with the Superclock 1 Mod & Black Gate Caps on the Transport. Am I losing out on a big difference in sound by not having the Superclock 2? Is the one I'm getting with the Superclock 1 much better than the stock Sony? Thanks for your help!
Superclock1 is quite old. I'm surprised that anyone has any of these left. The Superclock3 is out now and this is what I have been installing. The 2 was very good, much better than the 1.