One of the most popular 'Amazon-swords' the Echinodorus bleheri' can grow up to 50-60 cm in height and the mature plants can have up to 50 leaves, each growing around 3-6cm in size. Also known as Echinodorus paniculatus it's really easy to grow and will require little care for hobbyists making it perfect for beginners and up. Because this aquarium plant grows large, it's often used as a focal point so bear that in mind. However, in larger tanks, they look better placed behind stones.
In a CO2 infused tank, you'll be amazed at how quick new leaves grow and if you look carefully you will also see tiny oxygen bubbles coming from the leaves, another indication that it's growing fast.
Note: the picture is an example of the species you will receive and whilst the pot size will always be the same, every plant is unique and natural which means they vary in shape and size.