I worked as a Leaf Filter sales rep for about a year (in 2013). everything bad you have posted is true - and there's more.
At the Friday morning sales meetings the reps and managers sit around a table laughing about the sales they made - mostly who could come up with a better lie to get a customer's signature. The reason they install jobs so fast . . is so customers don't wise up and cancel - seriously!
The BOTTOM price managers can offer is $10 per foot plus $10 per corner.
(the rep loses his fat commission at this point) If you place an order, then try to cancel b4 install, they'll give you this price. Reps get paid 10% commission at $22/ft and, NOTICE this, HALF of the money YOU pay above $22/ft.