Some toy collectors like to display their toys unopened - boxed or carded.
I'm not one of those myself. I think toys are, first and foremost, for playing with and should be freed from their plastic and cardboard prisons. Especially Transformers, as they obviously can't be transformed when they're sealed. (Except for Bumper Battlers, the cheats!)
However, I do have a small number of unopened Transformers, typically because I think they look good displayed in the box, or in the case of a few, as boxed examples of particular series. (I would add, though, that I also have opened versions of those Transformers. )
I was just looking at the Animated Optimus vs Megatron DVD set and realised that it would make a nice boxed display piece. So my question is, what Transformers do you think make good display pieces in their original packaging?