Product review (5 stars): good unit - good price
After reading various reviews about this particular product and at least one other similar dryer vent, and after searching hardware stores and box home improvement stores, I found the Heartland dryer vent at Menard's for $12.95.  I also read that James Dulley, the home improvement columnist, has this particular dryer vent on his house.  I disassembled and inspected for flash marks (did some very light trimming) and possible quality problems, found none and set about installing this vent on my aluminum sided house.  As the 4" duct connection does not come attached, I pulled the staples from the old plastic louvered vent being replaced and used that 4" duct.  A bit of down sizing was necessary on the aluminum duct and only having 1/2" in which to insert the duct in the dryer vent was a bit unhandy, but it all worked out.  I sealed the duct to the dryer vent with clear door & window silicone and it seems to be joined and sealed just fine.  I am a little concerned about how thin the plastic at the screw holes is but once attached to the house I sealed the dryer vent to the aluminum siding with more silicone and I think this will support the vent at least as much as the mounting screws supplied with the unit, which are not very long by the way.  As this unit sits on the north side of my house I am going to leave it unpainted and see how it stands up to weather degredation.  Thus far (two weeks) I have noticed absolutely no lint being held to the interior parts of the vent and this is after cleaning the lint from my gas dryer and seeing much more than normal amounts of lint on the ground around the vent.  Don't know yet how effective this unit is at sealing out cold air but will find out this winter.  Judging from what I have read, if you want to try this type of dryer vent, be sure it is the Heartland dryer vent and not a look alike model which is often substituted and seems to generate a lot of quality/durability complaints.