Victory pre-purchase information and service was excellent. The unit arrived early and was exceptionally well packaged. Online installation instructions were great, no issues were encountered during the entire installation process. I opted for three 45 degree elbows and 12 ft of 8" ducting between the range hood and the remote blower. All ducting was 26 gauge steel, cradled by 3/4" metal strapping inside 3/4" foam rubber tubing. The blower was mounted on a solid 2x4 frame, using 4 isolation bolts and 3/4" thick foam rubber strips. Finally, two 33 degree elbows and a 1 ft duct between the remote blower and the roof vent cap. All seams (including the blower, which has some leaks) were sealed, using aluminum foil duct tape. This 600 CFM remote blower is exceptionally quiet. If I had to do it again, I would reduce the duct length by 50% The reason why I chose 18 ft overall (between the range hood and blower) was to have minimum blower noise, but that also came with a loss of some operational efficiency, e.g. There is no difference between fan Speed 3 and Speed 4. It was explained to me that at this length of duct work, the motor is pretty well maxed out at Speed 3, so Speed 4 will not supply any extra suction. Also, after adding the last two elbows plus the roof cap and back draft damper, these appear to have caused a further 20% loss in efficiency. This wasn't too noticeable on Speed 2 and 3, but Speed 1 was greatly impacted. My suggestion is, don't worry too much about blower noise (as I did) Keep the number of adjustable elbows to a minimum, 45 degrees or less, and keep the ductwork to a minimum length. This blower is very quiet and does not need a lot of distance from the range hood (10 ft total, including elbows, should probably be sufficient) One last comment - I will add a 24 VAC circuit to the remote blower, so than the main furnace fan will run in circulation mode whenever the range hood is turned on. With 4 vents in the kitchen/family room area, this will supply an extra boost to the remote blower. This was very noticeable when working in the attic and the air conditioner came on, pushing large quantities of cool air up the 8" duct and into the very hot attic!
All this being said, our Twister 42 with 600 CFM remote blower is performing beyond our expectations. It is a high end range hood, backed by cordial, professional and competent technical staff. It has been a pleasure working with Victory Range Hoods throughout this project.