Works well for me to put images on sublimation mugs. I no longer tighten the cup into the press as I found that if I just squeeze the two black handles together until the clip falls in, it is enough pressure to do the printing.
My only problem with doing prints on mugs was (a) to find a place where I could buy sublimating ink. It turned out to be from the US, and (b) putting the ink into a Epson Eco Tank inkjet printer and getting the inks to be recognised by the printer. A nerdy friend did that for me.