Here's a pic of my #3 with a tape measure placed on top of firebox. There is about 15.5 in clearance at the peak of fire box to top of smoker box. I only hang jerky from the top rack, but there is plenty of room for 6-8 in strips that I have.
If you plan on hanging sausages longer than 12 in, you might want to save up for a 3.5D, it is 8 in taller. Or the 4D, it is higher yet. Of course they all cost a lot more.
I will say the Analog #3 (like mine) works very well, don't see the need for PID. Not sure if the #3.5 or #4 come in the analog variety anymore.