Lots of people (although probably not from here) don't rate any Topower based power supplies whatsoever. Often they are associated with being cheap and the value end, that are sold at high prices due to fancy designs, colourful leds perhaps, and a nice box. Although I've never owned one myself partly due to those comments.
Many popular brands you see out there rebrand topower power supplies, such as Tagan, OCZ, Akasa. The innards may possibly be the same, but the brand will specify what features they want. I think they actually even had a webpage where anyone could do this and specify what they wanted, and how many psus they wanted.
Tagan actually had one of their models deemed unsafe by the finnish safety regulators or something. Oh I even found the thread
here.
I seem to recall lots of people having to RMA tagan's on some other uk based forums too (dont think they're very liked here so i won't mention names).
This is not to say that all topower based power supplies are bad of course, even though my post may seem to suggest that. There's better out there for the money (regarding the insides of it anyway).