Trader Joe's offering is great in the texture department. It's not that they're an especially good approximation of beef burgers. But they maintain their moisture and juiciness even after cooking or grilling. They come frozen, and they look like little pale hockey pucks before heating. Speaking of hockey...D'OH!
If anything, they're a little on the bland side, flavor-wise. Lacking any fancy combo of spices, TJ's kept things simple as far as added flair: just a little kosher salt and rosemary extract up in the mix. So you might want to dress these up a bit. I found them to taste better when cooked on our charcoal grill. Some good quality bread, cheddar cheese, Miracle Whip, mustard, and pepper really helped give them some gusto, too.
I think these were $3.49 for four raw burgers. So they're cheap, convenient, and juicy—we just weren't dazzled by the flavor, although I wouldn't say it's anything to complain about either. We'll go with double 3.5's on this one.
Bottom line: 7 out of 10.