Not too long ago Al and Ryan had a chance to play with a prototype USB 3.1 enclosure from ASUS and an add-in card with a controller from ASMedia.  The Tech Report also received the prototype USB 3.1 enclosure with two mSATA drives running in RAID-0 mode but they happened to have an ASUS Z97-A/USB 3.1 motherboard which has a built in port and ASMedia controller.  Their CrystalDiskMark results showed a ~75% boost in sequential read and write performance with 4K random write speeds also vastly increased.  That is not the highlight of their review however; ASUS provided a list of upcoming USB 3.1 releases from multiple vendors so you can now get an idea when you might want to upgrade to a board with USB 3.1 on it.

"Today, we're going to take our very first look at some USB 3.1 gear. Asus has supplied us with a drive enclosure and a matching motherboard, which will help us gauge the kinds of performance gains users can expect."

Here are some more Storage reviews from around the web: