I bought the non-ball core version off of speedcubeshop, the corner pieces can fall apart easily if dropped or falls on mat hard. If you like turning fast you will have to loosen it quite a bit and then it will corner twist easily. I give it 6/10 (my new GAN 14 is much better)
I am currently learning ZBLL and as long as you use a trainer (I use bestsiteever.net) you can learn them efficiently and quickly. I started last week and have 27 T cases memorized. Another tip is that the T and U cases have almost identical cases, so if you learn a T case you can also learn a U...
Are there any cool looking algorithms that are fun to do? I am also looking for any algorithms that can help scramble the cube faster. All of this will be on a 3x3.