The 251 name is the format and the size, a 2×2 measuring 51mm, which is a millimetre larger than most. That extra millimetre matters, because 2x2s are small and plenty of solvers find the standard 50mm cramped.
The GAN251 V2 has no magnets. Most people prefer magnets, and if you do, the 251 M range is where to look. What going without buys you is a lighter cube, no resistance at the start of a turn, and a considerably lower price.
The GAN251 V2 is built to GAN’s usual tolerances, which is the real argument for their simpler cubes. A cheap 2×2 from a lesser brand tends to be loose in one direction and tight in another, and that is what makes it frustrating instead of merely basic.
A sensible second cube to keep in a bag, or a first 2×2 for someone who has not decided how seriously they are taking this yet. For magnets and adjustment, compare the GAN251M Air and GAN251M Pro.



