Marble.com website has a great tool to help not only pick your countertop edge, but the colour as well. Click the edge you want, and voila, that edge is rotating in front of you in life-like 3D. Click on different colours to help you visualize the finished product.
Note: Not all edges will be offered by all countertop fabricators. Be sure to check with your designer or fabricator before setting your heart on a specific profile.