In Win 509
The second In Win case in this comparison is the 509, which is almost twice as expensive as the 303 and does not even come with fans. It is a big, luxurious case with a lot of internal space for an E-ATX motherboard, a lot of storage and many fans. You will have to purchase those separately. The four usb 3.0 connectors are worth mentioning, as well as the used sound dampening material.
Without fans we were unable to test the 509 in terms of cooling performance. The dampening material does its job: it is the quietest case, purely looking at the measurements of our built-in test hardware. However, we think that fans are a necessity at this price. As it stands, the 509 is a bit too expensive.