Those are certainly "different" interfaces, but I don't think that one can definitely say that one is "better" than the other. What does the Kindle do if there are multiple definitions for a word? Another benefit of the DR1000 is that one can have multiple dictionaries installed (eg, a "general-purpose" dictionary, and a number of "specialist" dictionaries for different subjects), and see the different definitions in the different dictionaries; something that the Kindle cannot do.
From the sound of it, both the Kindle and the DR1000 have "workable" systems for using dictionaries. We can all be happy about that, without having to claim that one is "better" than the other. It's not a "contest"

.