Not a rip-off if you learn to play by their rules, but not great either. I joined many, many years ago. The way I looked at it it was just a magazine subscription for a so-so hunting magazine. This was pre-internet, so I subscribed to about a dozen hunting and shooting magazines at the time. Not my favorite magazine, but the only one I still get because it is free.
I eventually got talked into a lifetime membership. I've been getting the magazine for years without paying a dime. If they stopped sending the magazine to me right now, I got my moneys worth from that alone years ago. Even with paying for the lifetime membership.
At first they were constantly sending me stuff without me ordering with the option to pay for it or return it. Just write "REFUSED" on the unopened package and put it back in your mail box. They end up paying shipping both ways. After doing that a few times they stopped and I've not gotten anything from them in years.
To be a product tester you have to fill out and send in an application. They will then send you a product to test. You fill out a form with some comments and mail it back. You keep the product. In order to get another item to test you have to re-apply each time. The first 2-3 items they sent me were pretty cheesy and cheap items. Some worked ok, others didn't, but none were very expensive. Once you have proven to be dependable and will actually test the products and do a writeup rather than just keep it they will start sending you better stuff. I ended up with a few decent knives, and hunting clothes. Jackets, pants, shirts, caps. etc.
I haven't applied to test anything in years and probably won't. I don't think they are ripping anyone off. But some are expecting more than they should., or don't understand how the product testing works.