Backpack cyclists, what's your bag?

[esoteric]

When I bought a new bag from Regatta a year ago I had no idea about size and I bought a 20L Brize II in Dusty Rose(pink) for £25. It's a great bag but it's too small for my liking. I was unsure about the size when it was delivered but decided to keep it. I'm interested in getting something new to replace it and I'm thinking 30L would be ideal.

In the main compartment I carry a beanie and a neck gaiter with my cycling jacket on top of that and my shirt for work on top of that and that takes about 50 to 70% of space depending how well compression holds. Some times I stuff a porridge pot and a yogurt inside too and that's all the space pretty much gone and now I have waterproof trousers to carry as well. My phone and pixel buds are in pockets inside the main compartment too and my gloves and other small pieces are outside in the mesh pockets and a charger in the outside zip pocket.

I just can't find a bag as good as this one that's bigger, and in typical cycling fashion adding "cycling" to the search also adds £100 to the price.

 

[Vandle]

What makes a cycling pack a cycling pack and not just a pack? I tried the Rapha ones and while they are good, they are small. I tried two. I use an Alpinestars one on my motorcycle which is excellent but had it absolutely years and cant find the same one online. Don't worry about a weather proof one as you can get generic rainproof and reflective covers cheap from ebay.
I hunted for ages for a one for work as I walk a decent distance in all weathers and sometimes need a full set of gym gear and sometimes my laptop - sometimes both. I ended up with a 30l Nike Storm Fit ADV pack. Ordered a few from them actually as they are free returns. Its weather resistant, has a compartment for wet gear, has 2 drink bottle holders, zips out flat. Being NIke its cheap too.