I think part of the reason we all like Tenyo are the mechanical effects. Things like Crystal Cleaver or Prison Box are just so clever. I could totally understand a collection only featuring the mechanical effects. But that said Tenyo also offers some great non mechanical (or less automated) effects that may rival the best mechanized effects out there.

Billscape falls into that category for me. I truly had no idea how it was done prior to purchasing it. It really was magical and I could not just say "ah it's some fancy gimmicked box". I just had no idea.

Same here. I remember watching the billscape video again and again and couldn't for the life of me figure out how it works. When I finally got one, I was really impressed! Granted it's not crystal cleaver or prison box. However, billscape fits in your pocket. As a result I perform it more often.