Your JDC Membership number will be validated and can only be used one time per year.
As a Premium member you get many extra practice applications a long with extended statistics and functionality on the website.
The extended statistics will give your practice an extra boost, comparing your sessions with previous months and follow your improvement.
But let us warn you: addiction for practice is hard to skip! Be hooked, be the best you can, be the beast, be on your way to pro!