I need to be able to get to the bottle without breaking cadence, and I'm afraid that if it were mounted to the boom I'd have to stop pedaling and sit up to reach it. Bladders are an option, but not at the top of my list because I'd prefer to not be attached to the trike. Plus, bladders can be a pain to refill and to clean. I have a nice Ztto cage mount and I had it on the rear stay, behind my shoulders. This position works well for my carbon shell seats, but on the trike it's so far back that I can barely reach it. Maybe I'll end up not using the Ztto in favor of a couple of high-tech hose clamps.