The Stuart started the war as a primary combat tank but after it entered combat against enemy armor it was quickly relegated to scout duties and to protect the flanks of medium tanks. It's gun proved very ineffective against German tanks and it's armor was very light in comparison. They did have a very high speed and were very reliable which earned them some praise from foreign countries using them. They had much more success in the Pacific theater against the Japanese who had much less anti armor weapons and weaker tanks. The Stuart could also pass over muddier jungle terrain that was impassible for the M4 Sherman. Since so many of them were produced at the start of the war, they continued to be used until the end, even after the M24, which had a much better 75mm gun, was introduced.
This is the American tier II tank. It is tied for the highest firepower with the T-46, though it has a slighly faster rate of fire and a quicker turret. But it is also very slow on mobility if not fully upgraded compared to its tier II counterparts. This tank can be used to battle head to head with any tank in its tier or lower, though it should stick to flanking tier III opponents, who will tear them apart if they go head to head. It is best to work in groups and concentrate firepower on one tank at a time.