Actually nothing happens when you stop, drinks don't budge! If you hit a brick wall then yes but stopping with brakes, no. Its like it has a seat belt! lol As far being in the way that depends on how big a drink you put in it and how wild a driving style you have. When you extend your arm to change gears your elbow comes towards you.. try it.I feel like this is a neat idea..... until you STOP. Not to mention will be in the way of your elbow whilst shifting.
Kinda prefer my car with no real usable cup holders, but I did get the one that sits down in where the original ones are, too bad the size is only so big to hold certain smaller cups. Now I have a Yeti coffee cup that fully closes and seals and when I go to work, I seal it up good and lean it in the back passenger foot well. No spills and I can drive how I want, and if I would like a sip, I un-do the cap, sip and re-lock it.