I wanted somewhere to carry food, phone and power bank when out on longer rides (rather than a jersey pocket) so I picked up a Topeak Toploader bag. I was concerned I may hit the bag with my knees when riding (which was what has had me umming and erring for the past few days), but it looks narrow enough to avoid this. I'll know once I get out on the bike. I should be able to open and close the zip on the bag one-handed while on the move which was one of my other criterium. And lastly, I'll be able to run a charging lead from the power bank to my Wahoo with the zip on the bag 99% closed as it closes from south to north (so to speak). I'm quite happy with my purchase. Now I just need to buy a new mount for my Wahoo that holds the head unit further away from the handlebars so I can fit a micro USB behind it when charging.