a ""box"" is nice for easy access, cool. for easy access also just strap something onto your handle bar
open the flap and all on hand. also very light.
I also agree EXCEPT... I can't mount a handlebar bag in front of the bar due to 4 crossing cables from brakes and shifters, and clip-on aero bar blocking access. I tried mounting a bag aft of the bar (folder so tall handlepost), but my knees would hit it when climbing standing. I did mount a front bag on my old road bike for additional space for lunch or rain jacket, etc, but it was not easy to access (zipper top, near back of bag):
