Shengshou was one of the first companies to produce the high-order cubes, such as the 8x8, 9x9, 10x10, and above. Before MoYu existed they earned a lot by selling a lot of 4x4 and 5x5 cubes.They rarely have any mechanism errors when first unpacked and throughout its lifetime, and its interlocking mechanism is great. Their cubes are usually reliable and they are pre-lubricated when you open it (though this means that you have to wipe off the excess oil).
People using Shengshou have achieved records in all the high-order cubes, and some cubers still use modded Shengshou puzzles and achieve super quick times with them.
Shengshou made the high-order cubes more popular and they were one of the first companies to move focus away from smaller cubes and produce bigger cubes that performed beyond the expectations of other inferior high-order puzzles made by other manufacturers. The highest order cube Shengshou makes is the 11x11x11.
Unfortunately, their 3x3 and their 2x2 cubes are not great speedcubes. They actually have poor corner cutting and the 2x2 "speed cube" is actually not suitable for speed cubing. The Shengshou 2x2 actually has a few hollow center pieces.
Shengshou was the first and only cube brand ever to produce the Elite Kilominx and the Gigamorphix.