Never been in a garden room, but know others who have been. As for bugs, I can tell you if you leave food your room or empty drink glasses, you will find ants in your room. Easy fix, take empties back to the bar when you leave. If you have room service, leave your dishes in the hall and someone will be around to get them.
We've always stayed in the garden room....never any bugs. If you leave sweet drinks out you might attract tiny tiny little ants...that is what I have read. We even hang our wet suits and still nothing. Besides your rarely in your room and there are beautiful views a step away :-) go and have fun!!!!