I'm really happy with their quality, but you'll have to judge that for yourself.
We're handling the boosting automatically in software. When the iron detects that it's under load, it maxxes out the power to the tip. It's incredibly responsive.
You're right, where you want that is with high thermal mass objects like ground planes. The difficult part is getting enough of a thermal bridge onto the material to really let the iron rip. It can dump a lot of power into a joint.