In order to achieve the 40-10G connections between the adjacent racks, we planned to buy some optical modules for our data center. Since AOC could provide a more cost-effective solution than normal transceivers + cables solutions, so I decided to pick that. Then I found that FS's 40G QSFP+ to 4x10G SFP+ breakout active optical cable might meet my demands. However, with no shopping experiences from FS before, I consulted with the account manager prudently at the beginning. She helped me to check the compatibility between my equipment and the AOCs that I planned to purchase. Quite impressed by their considerate services. Professional and trustworthy, I assumed. So I rest assured and placed my order immediately. Affordable prices and reasonable shipping postage. Lovely! We tested the cables after receiving the packages and used them for months. No compatibility issues in the long run.