If you are new to speed cubing then a good budget cube is the best place to start. Don't worry about magnets and lubricants!
Now you are looking for something with a bit more spice! Why not take a look at a magnetic cube?
A premium cube is perfect for competitions. These are the best of the best!
There is a range of larger cubes available from budget to premium magnetic.
Larger cubes add that extra challenge you've been looking for.