tkTable = Tk::TableMatrix in Perl/Tk. It was renamed since there was already a Tk::Table present.

TableMatrix does offer a decent boost in performance over other options in Tk. Is Tcl::Tk a bit faster? Sure, however for typical applications I would argue that the performance difference is not noticable -- at least, IMO. Most of the time, GUIs aren't really doing all that much. It's the application logic triggered by the GUI where you tend to get into trouble.