Topeak  Aero Wedge Pack DX

I bought this to replace an existing Camelback saddlebag (that I picked up to replace a broken Bontrager bag). I was looking for something with a durable connector for my bi-saddle. When I first looked at installing I wasn't sure it would fit given how my saddle is positioned on the seat post). I removed the saddle and seatpost (still attached) and saw that the composite connector fit and the saddlebag could be mounted. I am Glad I did. This bag, the Small, holds a replacement tube (I do run tubless but during a race its good to have the ultimate backup), tools, CO2 kit, electric mini-pump, chain links, quicklinks etc. and rubber gloves. Once installed it doesn't move around, is very aero. The outside, side-pockets are tight and I haven't figured out how to use them (yet). All in all this is a very effective and efficient bag for carrying my necessary items. With a second saddle rail connector it should be very easy to move from one bike to another,

I bought this to replace one I was using on my road bikes. What really attracted me to this was the ability to have it move easily between bikes by only adding another connecter. I like the size, the main pocket is large, but there are also side zippered pockets for miscellaneous items or cash. I carry two tubes, I run tubeless but have a a deep back wheel so I need two different size tubes, and 3 air cannisters as well as a multi-tool. I know I roll with a bit more kit than most, but I'm usually by myself and I want to be prepared. Finally, I like how secure it is on my bike. When I'm out of the saddle my other bag would sway, but this one is secure on the bike.

Good design and actually works OK with my dropper post. But...I returned it because it scraped the rear tire on my full-suspension mountain bike on bumpy downhills.