I really love the design of the system and way the bottle tucks in to the frame. I went with the 15oz bottle which is perfect. A bit tricky to get in and out while I'm moving but the good thing about that is the way it stays connected when I'm bombing. Highly recommend!

Twist bottle 450 is also available with the cap on the mouthpiece the same as model 590?

My 52cm gravel bike's frame is a tight squeeze when I'm running a half frame bag, so being able to still carry two bottles is great. The twist release makes getting the bottles a breeze to get out. Getting them back in their "cages" is literally a snap thanks to the strong magnets. The only downside I've found is that I liked them so much I had to buy additional mounts for the rest of my bikes

Nozzle needs to be covered and hard to get the last drop

Hi I love the concept, design & ease of use, however one of the bottle's lids leak when drinking from it. Cant squeeze it without water dripping out all over and drinking from the nozzle just sucks in air. I had to use a lid from another water bottle to resolve my issue. So i basically paid $40 for a super nice mounting system with a leaky bottle. :|