PCB questions...and concerns

Hi,

Fusion PCB can charge me 6cm X 6cm the same as 5cm X 10cm. I don’t mind, because I don’t want to cut things when I get 5cm X 10cm, if my design fits 6cm x 6cm.

Anyway, I saw that Fusion PCB always offer a service that if I paid $46 set up fee, I can choose the size by cm square. Any size. Is that true?

Thanks