Does anybody have experience with Venturi style showrheads?
Are they as good as advertising claims them to be.

The basic claim is that the showerhead areates the water, (increaces it's volume by mixing in air)
You can then reduce the GPM flow without sacraficing water pressure.
There are also claims that the areated water softens skin and hair.
They can get quite expensive for a good one.

Is this style showerhead worth it?

I have used a venturi style showerhead for a couple of years.  I have had no problems at all.  I had been concerned that the tiny outlet holes might clog but this does not seem to have happened even though I have had lots of plumbing work done at my house which must have sent a fair amount of detritus through the pipe to the shower head. 

I have regular low flow shower head in a second shower which by comparison seems to just trickle out the shower water.

The air flow creates makes the shower head a little more noisy than a regular showerhead but not to an extent that can be noticed outside the bathroom.

The brand I bought is manufactured by an Australian company e-co (ecoshower.com.au)

That animation is backwards relative to how this priciple is used in the showerhead.
The animation shows pressure and speed positivily correlated (in this case pressure goes down, so speed goes down)
If that animation flowed the other direction, (pressure increases), then the speed would increase.
In the animation the changing diameter of the pipe is used to change fluid pressure.
In a venturi showerhead air taking up volume causes an increase in pressure.

The animation parameter values can be varied by dragging on the yellow handles. Bernoulli's Principle states that as the speed of a moving fluid increases, the pressure within the fluid decreases (and vice-versa).