[Koha] Limitation of Koha

Hi, I would like ask a question, what is the limitation of Koha? 1. Collection size - How many books records can Koha handle? 2. Readers - how many readers can Koha handle? 3. Circulation - how much transaction can Koha handle per year? I found a an 2003 information about Nelsonville Public Library in Athens County, Ohio. The library has 7 branches, including a mobile book mobile. The library has 250,00 items and approximatley 650,00 issues per year. Any further information Anthony Mao