MEMS-based storage is a new, non-volatile storage technology currently under development. It promises fast data access, high throughput, high storage density, small physical size, low power consumption, and low entry costs. These properties make MEMS-based storage into a serious alternative to disk drives, in particular for mobile applications. The first generation of MEMS will only offer a fraction of the storage capacity of disks; therefore, we propose to integrate multiple MEMS devices into a MEMS storage enclosure, organizing them as a RAID Level 5 with multiple spares, to be used as the basic storage building block. This paper investigates the reliability of such an enclosure. We find that Mean Time To Failure is an inappropriate reliability metric for MEMS enclosures. We show that the reliability of the enclosures is appropriate for their economic lifetime if users choose not to replace failed MEMS storage components. In addition, we investigate the benefits of occasional, preventive maintenance of enclosures.