I will teach 7x7 here. I will first explain the concept of the approaches to 7x7 solving for beginners and advance as time goes on.
For beginners, the process is simple, but the sheer amount of pieces are often overwhelming. Do not worry about the pieces and focus on the approach: reducing it...
Currently, I have been using my Qiyi M Pro 2x2. It's actually pretty good for a budget cube. I saw that the YJ MGC2 Beta 2x2 (Ball Core and UV) was on sale for $13. Should I upgrade, or should I save my money and keep using my Qiyi M Pro?