I've never really cared for the DSD myself, but it's funny how we've gotten basically 3 verions of the same (sort of) figure, and some people made a 4th by removing the black coating of an original DSDroid.
I don't think we even had a Death Star Droid as kids, at least that I rrecall being handed down by my older brother, and so I'm pretty sure it sucked to us too since we had most of the original figures through Empire... I had most of the Jedi stuff then as that was more my time of collecting.
He does sort of suck... The POTF2 figure with the black chrome, which obviously was to represent a different character but basically the same, was pretty spiffy in its day. I have a handful of those and still pick it up if I see it cheap at toy shows and whatnot. And if you remove the black, you get one really chromed out DSD with usually black residue in the crannies that looks like grime and grease.
The first actual modern representation of the SC Droid wasn't bad though either. I thought it was a good likeness, and in some ways superior to the BAD since it has actual grime and wear deco to it. The BAD figure is fantastic, but basically a super clean version of the SC Droid.
I don't consider the CW Droid to be the same... There's differences in the design that go beyond animation compromises I think, so to me they're not from the same "robot family". But that figure is definitely in my collection as it's quite realistic looking too, and makes a cool sepaeratist smuggler guy. Mine just got an upgraded realistic Sep rifle, and he was ready to roll.