ezPoster 640, 600 series cannot be cascaded seamlessly. ezPoster 560, flex series can be cascaded seamlessly.
Supporting seamless cascade or not is a trade off of functionality and reliability. With seamless cascade support, multiple ezPosters can make a big screen without noticeable boarder between the posters, but it’s easy to cause edge pixel damage when doing the cascade setting up. Without seamless cascade support, the poster has a protective wall on the edge to prevent edge pixel damage, but it will show a black boarder between posters.
Whether or not to have the seamless feature depends on your usage. Our suggestion is that if you move the posters very often, 640 or 600 series will be better choice since it has better edge protection; if you install the screen on a relative stable location, 560 or flex series will be more suitable.