I have this set and here are my comments:
1. Picture quality is just so-so.
2. I watched the Cantonese track and in the episode when Kwok Jing met Wong Yung for the first time, that whole episode is in Mandarin, with no way of switching language tracks. I thought that it was a fluke. My parents have a set and it is the same thing. Sometimes...you can be watching an episode and then the language will switch for a few seconds...only to return back to the original one.
If picture quality is important to you...you're probably better off getting the one that was officially released by TVB. I just happened to purchase this set 2 months TVB released it. This set is not an offcial TVB release.