LEGO Technic App-Controlled Cat D11 Bulldozer 42131 Building Set for Adults (3,854 Pieces)

Fun and challenging build I really enjoyed it.

Another home run for Lego! Instructions are superb, almost without exception. There were no missing parts, and everything fit perfectly, though when marrying some of the larger assemblies together, you have to do a little finagling, but that should be expected on any model this complex. There was a moment of trepidation when the model was complete and I started it for the first time, but amazingly it worked perfectly!Yes, it is a lot of money but when you consider the amount of engineering hours that had to go into developing this monster and it's fairly limited market, plus the number of blocks needed to build, the price is really quite reasonable. You can trust Lego parts to fit together like they should without being loose or requiring a hammer and quality like that costs extra.This is not a model for the inexperienced or young and mechanical ability is a plus. Build time was about 26 hours - give or take - because I really didn't time myself.

The Lego D11 is an amazing Lego build hands down. It definitely ranks up there with one of the best builds I have done to date. It is a very technical build but not overly complicated in my book. The gearbox is amazing in how it works overall.The app does have some issues which has been reported by others. The fix for me was to uninstall the control app, install and everything worked as it should. Mind you, the original app install went through the testing phases without issue. The issue arose when the build was complete, and nothing would function. But as mentioned, uninstall and reinstall and you should be golden!

Hard to make it but worthy to make it.Awesome piece

I have browsed the various comments and have seen mostly positive comments about this build. I think it was great. I received all parts and the build was a success. However, no one thanked the master mind of this monstrosity in any comment that I could see. So thank you Markus Koosmann for your efforts in the design, engineering, and whatever else you and your staff did to get this to come to life. Your will probably never see this thank you but if you do, much appreciated.Vaughn in Maine

Super interesting to assemble, fun to play with (using the app), and it can actually be rebuilt into pretty much anything.

Set unavailable on main LEGO site. Was able to find and purchase at comparable price. Great value and the exact set I was looking for.

Well worth the money heck its lego. My 14 year old put this thing together and it was amazing to watch him run it afterwards. Wish i had stuff like that when i was his age. Once again very good product