I'm am always impressed with the conversion of objects to LEGO!
I'm a LEGO dad who opened this set two days ago. My son wanted the truck and the dinosaur even though he never saw the Toy Story movies.
For my part, we had our first apple and our first log top.
The marshmallow on a branch is funny and smart! It can really slides down the branch like when you overheat one over the fire!
Regarding 4+, I really like that this set has printed pieces and not stickers. It will last longer.
One more thing, remember that it could be your last chance to put your hands on the characters. Pixar confirmed that there won't be another Toy Story movie.
Construction time with a young child who helps me: 45 minutes