Looks really cool! Not sure if - 2 things...
1. rigid enough so that it does not significantly vibrate as this might change the point in the air envelope that is sampled and thus change the pressure vs calibration. Hope this one makes sense.
2. Not sure if it sticks out far enough to keep the air envelope at the sample point (trumpet on end of tube) from changing with the placement of your hands and shifting.
Now regards 1. above vibrations may average out, not sure how severe either of my concerns might be. I used a 3/8 in diameter dowell rod to support mine, it sticks out like a refueling probe on a jet
All that said, it may work great as is, just not sure.