Hope this is the place for a 'question' topic. I don't have much experience with different percs and was wondering if someone could explain the differences? Less on the design and appearance side, more on the actual effect it plays on the vapor? I haven't used or been around bongs or high[er] end bubblers for quite a while; since I stopped smoking. But filtration has changed vastly in the last ~10 years. At least affordable diffusion. What is actually taking place in the 'diffusion' process? Which have higher/lower levels of drag or resistance? Does it vary from one glass blower/manufacture to the next? As in, can one persons Showerhead create a different drag or result than the next persons Showerhead piece? Thanks, just hoping to learn/understand the process better.