Savotta backpack as carry-on (Ryanair / Wizzair)

Hi everyone,

I'm considering buying a Savotta backpack that would fit within the free personal item limits of low-cost airlines like Ryanair and Wizzair (officially 40 × 30 × 20 cm).

At the moment I'm looking at the Kahakka 25, Kahakka 15, and Niukka 20.

Has anyone here actually flown with any of these packs as a personal item and, if so, what was your experience? Did you ever have to put it into the airport sizer? Did you maybe managed to squeeze it to fit the limits?

Also, do you know of any good compression techniques that help reduce the pack's height? On paper, the Kahakka 25 and Niukka 20 are a few centimeters too tall, so I'm wondering if it's realistic to compress them enough when they're not fully packed.

I'd really appreciate hearing any real-world experiences. Thanks!