They're at £3 for a package of 12 right now online at Tesco. They are not huge - smaller than a golf-ball, each. We got all this veg stuff on sale about 10 days ago, and I think they cost less at that time. The only thing that was a bit weird about them was their texture. It kind of reminded the Daughter, texture-wise, of the inside of a hot dog, or maybe bologna. But at 150 calories for 3 of 'em (considered a serving), they're handy to have in the freezer. And we had them without any sort of sauce, just to see what they were like. I do think they'd do well in a nice tomato sauce. Or, as above, in a meatball sub.

Oh, yeah, I forgot to mention. We tried the Linda McCartney's Red Onion and Rosemary sausages the other day. They were nice. A bit bland, but for a meat-substitute not bad. (They do have soy in them, tho.) Could definitely taste the rosemary, not so much the onion. They were a package of 6 for £2. I'm not sure I'd get them again, but the Daughter really liked them. I miss the taste of the animal fat that would normally accompany a sausage.
I'm not sure the purpose of any of these is that they are any healthier than meat. It's just that you can avoid eating meat.
[Note to the reader: We are on a seriously calorie-restricted diet right now. So we get
really hungry. There are times when boiled shoe-leather would probably taste wonderful to us....]