What's the difference between these panniers
 

I'm shopping for panniers and have shortlisted a few Ortliebs but then came across Carradice gear and found this at Evans Cycles, and after checking the Carradice website found this bag which has the same name and is way cheaper, and afaics, differs in that there's only one securing strap rather than two for the closure flap.

I phoned Carradice to ask about this and they said that the bag they're selling is a newer version of the bag sold by Evans Cycles, but when I mentioned that the Evans price was significantly more and that the product photo on their website was different, the Carradice person said that the bag sold by Evans is higher quality.

How confusing - so the bag sold by Evans has been superceded by an inferior quality bag?