Lol! Fair enough!

YMMV I reckon. Or rather YSMV.

This is probably not extremely relevant, but we traded in our first Osprey Poco for a replacement at REI because the kiddo's straps were sewed off-center and it was giving me hip problems.

If you're just in the store for a little while, why not lock your helmet to the bike through the strap?

Thanks for all the replies. As mentioned, I am a huge Osprey fan when it comes to packs for hiking and even fastpacking (just started to dabble in that sport!). I am using a small Mountainsmith pack that I bought years ago... it has held up well for what I paid but its starting to show its age (zippers are starting to bind).

I am really caught between going back to a messenger-type bag, or trying something that has been mentioned above. Decisions, decisions....

I am super paranoid and would never leave my helmet where someone might come along and damage it. Especially since damage might not be visible. I leave the helmet on the head if there's no room in the pack.

I personally don't like the messenger bags for biking. I have had one significantly shift/rotate around my torso and it impaired my ability to steer since it was bumping my arms and handlebar.

Depending on how much you need to carry...I use the patagonia atom sling bag. Only 8L, but the shape means no sweaty back, the stabilizer strap means it stays put, and it holds the basics. It also has compression straps so you can strap down a jacket or something on the outside. I think they make a larger one as well. Smaller bags make you decide what you really need to carry, which can be a good thing. I also toss in a nylon backpack that folds into a small zipper compartment - in a pinch, I can layer it over the sling bag if I have something unexpected to carry.