tliebKS: I cannot give you any information at all on the agrifab, but I can do well enough on the Brinly pictured in your post. I happen to have that exact unit at my home.Sure..here is some pictures. The whole frame adjusts on the Brinly where the AgriFab has a rigid frame and you adjust the shanks. Depending on your crop, time of usage so you don't break off your plants appears to be the biggest limiting factor.
Here's a little background: My ground is heavy, red clay - or it was. It wouldn't even grow weeds about 7 years ago. However, over the years I had it plowed under every fall, and I've had double ground leaf & wood mulch dumped on top of the turned over ground. Then, I planted crimson clover seed for the winter. I also added several bags of agricultural pelleted lime to the soil. All this sat until the following spring.
Come spring, I'd use this Brinly Spring cultivator to rip up the crimson clover, and lay out my rows for the planting of sweet corn. My Ambrosia corn would get over 8 feet tall, with three to four ears per stalk. Even the neighboring farmers couldn't believe how well it was growing.
Anyway, as far as the cultivator was for my use, I was very pleased with it. I bought the extra feet for mine at my local Agri-supply as the Brinly's for the most part are not available. Purchase some plow bolts along with the feet of your choice, and you have a versatile cultivating tool that can bed up your plants too.
I think I have two or three different sizes of pointed feet, some "duck's feet", and some shovels. All of which work very well for me.