Hey everyone!
The following is a quote from the electric pattern forum here on RCU. It is the last line which is notable, that the goal is to achieve the power and performance of the YS; still the standard of pattern performance.

"The long awaited BJ Craft X-Drive contra unit is here!! I have been waiting for this unit to install in my Eternity. It arrived the other day and I am now back home and can post the first look.

This is is a beautiful drive unit. The machining and workmanship is really outstanding. This is a twin belt drive, direct coupled contradrive unit with no clutch nor planetary gear system. Read that as low maintenance like the Adverrun. I think the Adverrun is the benchmark these days for power and simplicity. The X-Drive looks like it takes things a step further. It came with the custom BJ Force outrunner motor, beautiful pre-cut CF spinner, precise lightweight AL backplate and mounting system for the Eternity.

I did a weight check and it looks to be about equivalent to the first gen Adverrun at 655g. However, this may be even more powerful than that beast. If so, I can’t wait to get it flying.

B.J. said his goal was to match YS power and performance. Based on my Adverrun experience I think this is achievable."