The price is steep. This will be a problem for low budget projects. However, there are other options, as always. Tunecharger 4.3 and the new chip CTP 4.3 does a similar job for anyone skilled enough to make its own circuit scaling for the desired output. Besides, this chip i really smart too. It also feature MPPT, making it perhaps the cheapest and smartest option when it comes to homebrew charging solutions.
I should have said first that I'm not affiliated with this team in any way.
But check www.tunecharger.com and take a look at the product's datasheet, you'll see a lot of potential out there.
Claude