Because both adapters have provisions for standard 3½" drive mounting, either will work fine in most manufacturers cases. Whether it uses basic screw-in bays, drive rails or other tool-less attachments, such as these Cooler Master drive carriages, just about any mounting type will work. For the 990 bracket to fit here I did have to remove two of the pins, since the Cooler Master trays come with rubber isolated pins preinstalled. But other than that minor change, both units fit just fine in my case.
Both of these Icy Dock adapters allow the use of a 2½" drive in a standard 3½" mounting, the difference is in their intended environment. The 882 model is designed as a converter, it accepts one 2½" drive and for all intents and purposes, transforms it into one 3½" drive. This is most useful for installing a smaller notebook hard drive or solid state drive into a 3½" external drive enclosure, hot-swap drive bay or other enterprise environment where the mounting provisions and SATA port placement are critical. The 990 bracket is designed to be used in a standard desktop or tower computer case, where connector location is not important and lighter weight, simpler installation and the ability to carry twice as many drives is of greater usefulness. It's perfect for holding two striped SSDs in a RAID0 array.
Both units are well made and have a simple yet effective design construction. The spring loaded tabs on the 990 bracket in particular are fairly unique, I have not seen this style of tool-less installation method used on any other drive adapter. And the pins are removable if you'd like to use it with drive rails or other mounting system your case may possess. Similarly the 882 converter can be used nearly anywhere a standard 3½" drive will work, the only downside being that it accepts only one drive per enclosure, and the extra electronics present a potential point of failure.
Either adapter will set you back around $15 to $20, a small price to pay in order to securely locate that expensive new solid state drive in your older enclosure. And some manufacturers or online retailers are even including an Icy Dock unit bundled with their drives. With the growing popularity among enthusiasts for fast SSDs, yet still fairly limited mounting provisions even in modern desktop cases, aftermarket adapters like these Icy Dock models are sure to be big sellers.
OCIA.net has awarded the Icy Dock 2½" to 3½" drive adapters our Gold Seal of Approval.