This item kept going in and out of my cart for about six months, because I was happy to read the stellar reviews, but I kept doubting if this would really hold my kids attention or not. We have Lego's, but they only play with them once in awhile. How would this Zoob set be any different?I finally gave in and decided to give it a try. If my kids didn't like it, surely another family would enjoy them, so I'd give them away. I'm happy to say it has been a huge hit! They have played with them every day since they got them. I have a wide range of ages in my home and even the older ones have enjoyed building some contraptions with their younger siblings. They have made all kinds of things. Boys have made the usual boy things, such as swords, shields, tightrope, steering wheels with gas pedals, and so on. Girls have made crowns, necklaces, various pies/cakes, American Girl doll accessories, and so forth. Of course, they have made most of the ideas that come with the package, but their imagination has taken off to create things I would have never guessed would be possible with this little set. All kinds of imagination goes on with the Zoob set! Unlike Lego's, these pieces are movable and I believe that has been the main reason these are a hit with the kids.One thing I especially appreciate about this set over something like K'Nex would be the size. They are the perfect size for little and big hands, while also not being a choke hazard for small babies and toddlers. I think this is important to note, because although it warns it is a choke hazard for children under three years old, I believe these pieces would be difficult for a baby/toddler to choke on. My kids have swallowed things they weren't suppose to, but never anything the size of these pieces. I believe the gag reflex would happen quickly and it would be spit out. Each piece is approximately 2 1/2" x 3/4" x 5/8". Not every piece is exactly alike, but this is an approximate size for all of them to give you an idea. Of course, each person needs to use their own judgment for their own children.If my kids were to complain about anything, I'd say they wish they had more pieces! If you have a couple children who would be playing with this, I'd say this size set would be sufficient, but any more children than that and you might find yourself buying another set. I am definitely glad I didn't buy a smaller set than this one. I'm now considering the other Zoob sets that have a specific purpose in order to add onto this one.I am surprised this isn't found in local stores, but I'm glad I took a chance with it here on Amazon. Hope this review helps you in your decision.Update: I would still recommend these, but I have since found that the Zoob's which clip on do break off into a small penny-sized piece. So do be aware of that for both choking hazards and durability.