You could also try 2.5's CellTableBuilder (where you could easily make the buttons on the upper right corner dynamic by adding Columns) but it'd probably be more complicated.
Ralf,GIven that you don't know how many you intend to display, and that there could be a large number of them, I'd go with Cell. However, if you are making just a few, with rich eventing/interactions, then I'd do UiBinder.
I'd still be keen to know measured benchmarks for these widget types.