Failing harddisk enclosure

I brought an hard disk enclosure back and I was in HK, and used it on a new 500Gb hard disk. I realized that the power switch part of the enclosure seems to be a bit flicky, but still gave it a try. The thing ran OK for a week and then failed last night. So I have to yank it out.

I am not saying that this brand has problem, and in fact, I brought 2 same brand enclosure from the same store A-Grade. The other one worked very well.

It's just too bad that I was too busy during my Hong Kong trip that I didn't get time to test everything as exhausted as I should be.