Concerns about using kirby for a medium size website that will grow over time

You can have a look at my use cases:

http://ruderclub-nuertingen.de
Still using Kirby 1, at the moment working on updating to Kirby 2. There are many invisible pages behind which are just displayed as data (at the moment ~300 pages in total).

http://wagner-ewar.de
The product folder alone holds all ~250 products. Only page loading issue comes by design (at the product line, where all products of one line are displayed on the same page without pagination…). Also doing many connections in between pages with lots of searching and filtering through products.

http://volt-gear.com
Custom e-commerce solution written completely in Kirby. Not 30 product pages by now, but that wouldn’t be a problem at all here.

Hope I could help you with this!