Well, I haven't been here for a long time and have been away from my woodworking for a while. Life happens sometimes.
Anyway, I'm finally finishing up my shop and am about to pull the trigger on my ductwork and auto gate system. It seems that Ecogate has eliminated its "economy" gate system, and the only reasonably priced systems now are GrnGate, and iVac systems.
I would like to make sure that there is not a third alternative available other than making my own that I should be considering, and which of the two aforementioned systems are preferable over the other.

My ducting will be 6" to within close proximity of my tools, and the necked down to 4" so I plan to use 4" gates.

thanks in advance for any suggestions.
Jonathan