Maximum number of prods/pages

[shoplite]

We're using latest version of Pro. The spec shows "Unrestricted Number of
Products" What is the practical limit for number of products and pages. Is
this purely a performance issue (a function of the Operating System and/or
type of server) . I guess the question really is; as we load up on
products/pages when will we see a performance degradation and how is the
best way to test this?.
Tks,
Richard