ADATA is quite good in my person opinion. I have two of their external hard drives ;
1: SH93 500GB - Had this one for 7+ years now? Hasn't failed yet
2: HD650 1TB - Had this one for 3 years now? Hasn't failed yet.
I've had problems with Western Digital failing before...
Though most things are due to quality control and standards, it's usually the luck of the draw sometimes... you just never really know.