LEGO 42100 Technic Control Liebherr R 9800 RC Excavator, Remote App Controlled Advanced Construction Set, with Interactive Motors

Great lego set for the price. I have been a fan of lego since my childhood days. I stopped buying lego in the middle as I got busy and didn't have time to work on a set. I recently came back to lego after a long hiatus and decided to get this set as I wanted something complicated and challenging. I absolutely adored this set it was a nice challenge but not too overbearing the motors and hubs worked great exactly 1000 steps. And it can be controlled via the app. The set was a bit expensive than I liked but it is well worth the money. My only gripe is that the digger bucket was not like the original liebherr so it couldn't dig stuff but still a good set all round I recommend this set to seasoned and veteran lego builders who want a challenge.

Great model

Built it for when the grandkids can visit again after C19. Also, I was getting bored and wanted a mini project, so this was my 71st birthday present. I thoroughly enjoyed building the kit. The instructions are very clear and you can't go wrong. Even so, I reckon it took probably 25-30 hours to complete. The programming aspect built into the Control+ app is superb. The round 'stone bricks' supplied with the kit are next to useless. However, the excavator works very well in picking up gravel in my garden. All in all, I'd say the kit is worth every penny of the necessary high price. I'm looking forward to lego bringing out similar large technic RC kits such as this one.

Wow! what a model. I got it at the lowest discount price Amazon offered it at, and it was worth every penny. It took me around 4 days to build, about 20 - 24 hours total. I must just say you need an up-to-date smart phone to operate this model. Check before you buy by downloading the "Lego Power Go" app. to your phone (free). Having built the model (quite a challenge, and I am an experienced Lego builder), then you can control the model from the app. and take on various "challenges" in the app. Looks great as a display model and has lots of play potential. If you can afford it then buy it. You will not be disappointed.

My favourite Lego Technic build so far. Every step was interesting and without the interminable repetitive steps that some sets require. As the very large piece came together, there were rewards all along the way. Each part of the structure was interesting to build and could be tested before the next part commenced. Loved every second of building it; it’s very therapeutic and relaxing building Lego Technic and the finished megastructure looks incredible and works brilliantly. An amazing achievement from Lego.

Probably the best Lego Technic set around. Great quality so assembles really securely. Very complex build but easy enough with lots of clear illustrations and instructions. Control from you phone with Bluetooth and you can even pre-progam a whole series of moves. A bit pricey but no regrets. Thousands of pieces but be careful not to lose any during build as Lego are so mean they count almost to the last tiny link and don't give you a few spare just in case.

I thought i'd write this review just in case anyone was having a similar issue with connecting to the hubs. I've seen some feedback saying it could be the wrong motor, the app or bluetooth connectivity. I couldn't find the solution for my connectivity issues, so i thought i'd share what I've experienced. I've just completed stage 1 of the build (the base section) at which point the instruction manual (on pg234) asks you to test the hub connection using the control plus app. I then downloaded the app and began testing the hub. I found the app not intuitive to use as it wanted me to connect to the upper hub which I hadn't progressed to at this point. I tried various things to get to the lower section, but the app simply wouldn't allow testing on the base section. I tried to reach out to Lego via email, but apparently its fairly long wait to hear back from them ~11days. So what I've done is to take out all remaining motors and hub and connect those up (randomly). Please see the photos I've attached. Then I've gone back into the app and gone through connection testing. It asks you again to connect to the upper hub first and then you can see which motors are in the wrong ports. After correcting, it instructs you to turn on the lower hub at which point it shows connected to both hubs. It then went through 2 firmware updates for the upper and then the lower hub. After which it goes through a calibration mode. At this point I stopped the port testing as everything seemed to work fine. Bottom line for me is the app doesn't work very well, but hopefully the rest of the build goes ok. Good luck to the rest of you!

This is a splendid model, with most photos of it not doing it justice, but has some tricky bits during the build, especially if you are trying to get as perfect a result as possible (with the injection flaws hidden). In particular, the orientation of pieces is often unobvious when you start making a sub-assembly. If you have electrical problems, be sure to check that you have wired everything right, and that you are using fresh batteries (especially the first time you start a control+ hub up, when it does a firmware update). Using a Huawei P30 Lite to run the app works absolutely fine. Overall, I'm glad I got this despite it not having as much mechanical complexity as some other recent mega-kits.