I've used my EZ-Vees to carry quite a lot of lumber and ripped plywood on my Mini, as well as a rolled up carpet, it works really well.
I didn't find the EZ-Vees to flex that much more than the Good Boy version, but then my boats are all pretty short. I could see that it would be different on longer boats. The Good Boy uses 2 inch square by 1/8 thick aluminum tube - the EZ-Vee has 1-1/2 inch square by 1/8 thick tube with an X-shaped internal reinforcement.
Kayak Carrier Kits
Pull-Up Strap Handle Kit
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