A little flimsy.. it doesn't actually break, but it does come apart easily if you pull the supplied lanyard (don't do this!) when extracting it from a tight USB socket. This maybe a concern for mobile users though.
Works well on Class 4 Micro SDs, but had recoverable errors writing to Class 10 Micro SDs over 4GB (it heated up a fair bit). So, I'd not recommend it for larger sized Class 10's (I didn't have any Class 6 & 8 to test).
But, it's also only 3.99. :) 4 stars.