Even after a couple of years, I still find myself occasionally fingering a G chord on the uke when I see the 'D' on a piece of music (etc.), but not all that often, and it's very minor compared to the advantage you have of already knowing the fingering positions.
The transposition may take a while, and the lack of the lower strings can be a little confusing at times, but you already knowing the fingering patterns for chords will be a really big advantage, and you'll be playing comfortably in no time. Have fun!