I bought the self build kit as a joint present for my 13yr, 11yr old sons (and myself) for Christmas. Took us about 3 days, 3 or 4 hours per day off and on to build it together. The boys really enjoyed building it and learning about the differential and how the shocks worked and filled with oil.
Starting the car in December outside was a challenge on account of it being too cold. We found this guide on line which properly explained how the carburetor works and how to set it up https://www.nitrotek.co.uk/blog/2015/12/06/the-definitive-10-step-guide-on-how-to-start-your-nitro-rc-car/ but still struggled. Eventually I found that heating the engine block up with a hair dryer to get it warned up made it easier to get it going and run the engine in.
Once we'd got it going we had to fiddle with a combination of the low idle and throttle adjustment on the controller to prevent it driving off on it's own.
Now in lockdown in spring (bit Warner) it's been great fun getting it going again on a playing fields taking it in turns. It's pretty fast and quite easily copes on a bumpy grassy field bombing around.
All in all if you want a project and are happy to fiddle with it to get it going and are interested in learning about RC cars and how they work then I'd recommend this as a great way to while away many an afternoon with the kids.

very good buggy, very fast, much fun making it. a lot of plastic parts.