This set of rainbow arcs is a fantastic economical dupe for the Grimms rainbow. The size is large enough to try out many of the ball run ideas. The wood is sturdy feeling and dyed rather than painted so play won't chip it.

I got these for my grandkids because I prefer simple wooden toys that spark their creativity. This set comes in a wide selection of colors which I really like. The toys are smaller than I expected from the pictures, but they turned out to be a perfect size for young children to handle and play with. The quality of the wood is generally good, though not as smooth as I would prefer. They've been sanded, but it feels like they could use a bit more fine finishing to make them smoother to the touch.
My only concern came when my 3-year-old grandson, who also has a balance board, was about to stand on the largest half-circle piece. I was worried it might break under his weight. Thankfully, I intervened before he tried. These are definitely more suitable for stacking and light play rather than bearing weight. Overall, they're nice toys that encourage imaginative play.

I know that as the popularity of these rainbow toys has grown others have come out with more affordable versions, but this one is absolutely worth it!! It's on par with the quality of the popular brand name rainbow stacker, and it's beautiful!! The colors are fantastic, and it's super sturdy. This set also comes with a little wooden ball (maybe 2" diameter) that we plan to use to make a skee ball game!! We'll probably wind up pairing this rainbow stacker with out nugget to make a bunch of games, and to make rainbow stacker marble runs with the little ball.
This stacker is great!! Highly recommend!

This is a huge rainbow. My 5 year old loves it. She has a smaller version with the flat rectangles and the half circle pieces that she loves also. She was super excited to have the bigger one. The pieces are well made, the paint job is well done and it fits together perfectly.

Extended ROY G. BIV in 12-pieces

I love nesting dolls and rainbows.
This large rainbow toy is GORGEOUS and I have not the heart to let my kids keep it.
The wood is soft and the pieces are completely painted.
The rainbow can be stacked in different arrangements.
Additionally, it can be used on the bookshelf and adds a playful whimsy to any environment.
Lovely addition to my collection.