I know I want a Synik because I want a bag with the laptop compartment of my Luminary and the water bottle pocket of my Synapse, and definitely a little bigger. I've been worried that 22L won't be enough -- but WHY have I been worried? My L15 is a perfect bag for an overnight trip, so surely 8 more liters will be plenty, even if it's divided into pockets?
I did an experiment and figured it out. Here's how packed for my last overnight train trip:
One change of clothes in yellow cube, pajamas in original SE, TT with bedside stuff, sandals, travel mug, toiletries, ZTSB, en-route needs in Nordic SE. Also, my laptop, not shown.
Here's how it looks packed in the L15:
It's packed to the gills. I could maybe stuff a washcloth in there. But it still looks great and feels comfortable.
Then I packed it in my S19.
Is there more leftover room? Yes. I could definitely pack it with more. The problem is, I don't like the way it looks when it's packed full. It's just an aesthetic preference.
That was my revelation.
Would a frame sheet help? Maybe. But I looked at photos of the S22, and I prefer it underpacked, too.
And! I further extended this thinking to my A30 which I only like to carry when it's packed full! On my last 3-day trip, I packed extra stuff just to fill up the bag!
I have preferences for how much to fill or not fill other bags, too. In fact, my Luminary is the only bag that I like both when it's nearly empty and when it's completely full.
Here's where this leads me. I want a bag with externally accessible compartments for my laptop and water bottle: a Synik. And I want to carry about 20 L of stuff, so the 22 should be fine... But I aesthetically prefer the Synapse underpacked so I'm definitely going to buy an S30!
This took me a week of doubt and uncertainty, and I figured I can't be the only one who doesn't know this about themselves. So here ya go, internet!