I bought this set for my 6+ year old son - he'd been wanting it for some time.
He was fine assembling the parts together to build each carriage and the locomotive, provided I kept and eye on him - picking up the odd missed part. (best not to have any other distractions in the background)
The trouble started trying to get the remote control to authenticate with the hub controller, located in the locomotive, that runs the motor assembly. Given there is next to no written explanation in the provided assembly guides / instructions on what the various LED light colours mean (there are multiple colours to confuse you) on the Hub, it took more than 20 mins to get the remote controller to authenticate e.g. green LED on both the controller and the hub controller (Hub 88009).
The motor unit is quite powerful, so much so, when going at full speed, the train derails itself spectacularly!!
There is no sleep (automatic power down mode) so the Hub controller will drain a new set of AAA batteries doing nothing in a day if you don't shut it off - you won't find these instructions in the supplied documentation - tried Lego forums.)
The real headache started when trying to authenticate the Apple IOS (iPAD) Powered Up App. App installed fine, but the user interface is seriously lacking - it becomes apparent from playing with the App that Lego don't get software and really need help writing a better user interface. (perhaps they got a 3rd party to write this one?)
We tried multiple times to authenticate the Hub controller to the iPAD App, each time the App wanted to download new firmware to the Hub - that's OK, but being a slow Bluetooth connection it take 10-20 minutes (Patients is a virtue here). On three occasions the iPAD Powered Up App crashed during the download process, first at 88%, the second at 15% and the 3rd at 76%. After rebooting the iPAD it worked a 4th time - taking approximately 18 mins. Wow - way slow! Wasted over an hour!!
(Be prepared for the App to crash and leave your train running - with no way to control it - the supplied remote controller needs to be re-authenticated - else grab the train and hold down the button for the Hub controller until shuts off.)
When using the Apple IOS iPAD Powered Up App; selecting the 60197 soft button you get into the control buttons for the train set. Of which 3 are useful. The Rest seem to control future functions that don't exist (yet) - really disappointing as there looks to be some really fun features.
Living in New Zealand the local retailers tend to be clueless on most of the Lego product range, let alone questions about why things don't work or where can I buy the other enhancements for the train set. Your only lifeline here are the various Lego forums. (Lego documentation is largely silent on the various functions on the 'green' Hub button let alone things you can buy to add extra fun.)
There is a lot of potential here, Lego just doesn't seem to recognise the potential value - yet.
But please fix a few things, 1st - the hub needs a simple power off button. 2nd it needs to go to sleep (power down) if it hasn't been used for more than 15 mins. AAA batteries aren't cheap!! And that Hub loves batteries like no tomorrow.
3rd, Where are the instructions on how to use and operate the 88009 Powered UP Hub?
4th, the Apple IOS Powered Up App needs a better user interface design, run faster and stability testing against common in-use Apple IOS releases
5th, Please thoroughly test your software (SW) and firmware (FW) - it's buggy - Writing great SW/FW isn't like designing and injection molding a plastic brick!!
(Cautionary note - keep other Bluetooth devices away from the Hub and remote controller - things go a bit awry when they all get close together.)
Last note, the build quality, look and feel of Lego blocks and the Lego system is second to none (just the SW needs some investment.)