mwave offers the Sans Digital 4-Bay External eSATA / USB 3.0 HDD Enclosure, model no. MS4UT+, for $181.99 with free shipping. That's the lowest total price we could find by $11. This tower allows you to configure up to four hard drives in a RAID array (RAID 0, 1, 1+0, 3, and 5) and access them via an eSATA port.