I'm sure there are lots of folks watching these threads.
My question,
This style does not circulate the water, does this make a difference to the end product?
Yes and no.
There is a natural slow circulation in the water that is created when the warmer and cooler water sort of battle each other. These temperature differences can be just a degree or two.
When larger items are in the bath this can inhibit this circulation. That is when a water circulator is more helpful.
Also when using a crock pot like I do for example. The heating element creates fairly even heating through the entire bottom of the pot.
When using a device like pz has the circulation is more important because the heating element is just in one spot of the water.
I use a cheap aquarium pump and air bubble to stimulate water movement when using my DSV.
And there is one caveat to having a water circulator. You will have much more water evaporation. So adding water to the pot will happen more often.