Like others, we got this at Costco for our 5 year old and he was so excited to see it Christmas morning. On second trip around the block, the chain came off. Manual was good for repairing this, and it took about 15 minutes. However, on the next trip out, the driveline seized up. Took it apart again and found that the set screws holding the rear axle cog in place were not tight. Tightened those up and checked other hardware, finding all to be hand tightened at best. Thought this had it fixed, but on subsequent trips, found that the bottom bracket fitting comes loose. Requires a special bike tool to fix. Bought that part and a crank puller. Now that things are all tight, we should be good to go.
Saw these online for twice what Costco was charging. Had I paid the greater amount, I would be quite upset. It is bad enough even at the price paid and frustrating for not only us but our son as well.
If you buy one of these, check every nut, bolt, set screw and even the chain alignment and tension. It is obvious that these are not inspected well at the factory. Had I seen these most recent reviews, I would have passed. If you are not handy and somewhat mechanically inclined, stay away.