Although Rubik's was the inventor of the 3x3 speed cube  that doesn't necessarily mean he perfected the cube. In 1981 a company called Eastsheen began to produce their own version of the "Rubik's cube." EastSheen used a different inner mechanism for their puzzles and through a lot of hard work was able to produce a product BETTER than Rubik's cubes. Eastsheen calls their cubes "Intellectual cubes" since the term Rubik's cube is obviously copyrighted.

Intellectual cubes are known for their "out of the box" ready to play ability, meaning you could just pick up a brand new EastSheen cube and it would turn great, unlike the Rubik's brand cubes which require a lubricant and weeks/months of work to break in. Eastsheen is not as well known as the Rubik's company, which is probably why Rubik's still has any business whatsoever. From personal experience, anyone who uses an Eastsheen cube prefers it over the Rubik's and switches to Eastsheen cubes entirely.

There is one notable disadvantage to the Eastsheen cubes however, the distributors of the Eastsheen cubes are mostly located in China or Australia, so anyone wanting to buy an Eastsheen cube for the United States should expect to wait quite a while for your cubes to be delivered. Usual delivery time from a Chinese dealer is anywhere from four to six weeks, of course there are options to pay 3x3 speed cube for expedited shipping which would take anywhere from two weeks to seven days.

So, if you are looking to buy a cube just for fun or you are a seasoned veteran when it comes to the cube, you should always consider EastSheen cubes as an alternative to the Rubik's brand cube.