Almost as good as Top Gear? Tough call.
Visually, watching DS9 i fell in love with the works of
Jonathan West,
ASC. So, if he's at the helm, it will look great.
In terms of overall entertainment/rewatchability value, it's a tough call:
-The X-Files. I watched the Pilot the other day and was just amazed how brilliant it holds up after almost 20 years.
-Star Trek: Deep Space Nine from mid-second season to the end. They learned all the lessons they could from Babylon 5 and produced the second-best sci-fi series ever.
-Firefly. Never lived to see a second season, but it definitely is one of the, if not the best TV series ever. Or at least, it could have been.
-NCIS starting from season three.
and, of course:
Der Kommissar. Still the best crime/police procedural ever.
-Die Zwei (german dub of "The Persuaders!", see below).
I suspect the british "Life On Mars" will join this ranks soon, but as i've only watched two episodes so far, it's too early to tell.
Not necessarily, The Office is a huge hit for example. But anytime you try to copy a show from someone else it loses something in translation.
There is at least one example of a show actually gaining from dubbing:
The Persuaders!. Some non-wiki sources even claim that Rainer Brandt, the author of the german dubbing, was already hired as the head writer for a planned second season when Roger Moore landed the role of James Bond and the series thus ended. The series features some great cars, too, so you should watch it.