Bought my grizzly cyclone dec 08 but couldnt afford the ductwork untill dec 09. gave me plenty of time to concider duct design. " Bills cyclone" web page has lots of info.
my take on it: keep the ducts as large as possible for as long as u can. if and when you do get down to 4" plastic, try using stickey foil tape inside and out of the pipe with a screw or bolt to connect the 2 for a ground.
if u stay with a 7 or 6" duct, there's a huge diff. in volume when u bush that pipe down to 2.25" ( shop vac hose) your shop vac will have more suction than the dust system.big impeller=big duct
I started my woodshop in 1988 but never felt i needed a DCS untill i started turning lures a few years ago. wrong.shulda done it sooner .cough cough.
GF
