[cm3]

I also prefer Qt but starting with Qt4 it imposes a minimum memory overhead of 25MiB to 30MiB for even a simple single window application with nothing in it. QML is likely higher. I don't like Gtk3 but they don't have this particular disadvantage. It's too much overhead and I haven't found a fix.

[fla]

Yes that's one of the downside. Also, the binaries can get fat really quick. Especially when you link statically with some of the Qt components.

I guess it's a fair trade-off when you target today's desktop systems. Otherwise, it might worth looking at Qt for Embedded Linux.