"This was my son's 'big' Christmas present this year, and with the price point, we expected this would be a really great set. But the reality is, it's just... okay.
My son's biggest complaint is the small amount of track that comes with it. The single loop you can make creates curves that the train can barely handle without derailing. He asked for extra track for his birthday, so I'm on the site to purchase some and am finding pretty dismal reviews for the flex track, so I'm discouraged.
Second, the key pieces that hold the power function element into the locomotive simply don't fit well. As in, no matter how well you push them into place, they will simply pop out again (literally popping out!) The connectors simply don't lock into place like Legos usually do. This is very frustrating and obviously causes issues with the train running. You have to be verrrrry gentle with the train or the piece pops out and you're done.
Lastly, and this is my complaint not his, is that the train emits a very high-pitched whine when on. I suspect if we had a dog it would be very problematic. Is this normal?? It's incredibly annoying, even from an adjacent room.
Overall, I'm very disappointed with this and I'm not sure I'd sink money into another Lego train."