Cacti as a crop

Do any of you grow cacti for food (fruits and tunas)?

I live in a place with cold winters. So, it's more of a challenge to find varieties suited for these purposes here. However, it seems to be possible.

Here's a list of cacti I found from Cold Hardy Cactus that seem like they could be pretty nice for edible gardens (even in the north):

• Coryphantha sulcata Pineapple Pincushion (zone 5; tasty green berries all winter)
• Echinocereus triglochidiatus v. gonacanthus 'White Sands' (zone 5; large, juicy fruits; clumps quickly; lots of long-lasting flowers)
• Echinocereus triglochidiatus v. inermis (zone 4; spineless; forms heads quickly; red fruit)
• Escobaria missouriensis (zone 2; red berries that persist all winter)
• Opuntia humifusa (zone ~4; Eastern Prickly Pear)
• Opuntia hybrid 'Eastern Star' Eastern Star Plains Prickly Pear (zone 4; red, juicy fruit; 8”x48”)
• Opuntia imbricata v. arborescens (Colorado Tree Cholla) (zone 5; 60”x72”; red flowers; green fruit)
• Opuntia kleiniae (Pencil Cholla Tree Cactus) (zone 5; abundant green fruit; 5’x4’; pinkish flowers)
• Opuntia macrorhiza (zone 4; yellow flowers; abundant red fruit)
• Opuntia phaeacantha 'Mesa Sky' (zone 5; very heavy fruit production; 12”x48”)
• Opuntia phaeacantha (Prickly Pear Cactus) (zone 3; vigorous grower of large, red, tasty fruit; 8”x36”; yellow flowers)
• Opuntia woodsii (zone 4; abundance of large, red fruit; blue pads; salmon flowers; 10”x60”)

Does anyone know which ones of these have edible leaves/pads/tunas? It's possible that they all do, although I'm not sure. I've heard that the pads of most kinds of cactus are edible (but some aren't). Are the fruits all edible? I've also heard that most cactus fruits are edible.

If you've tried any of these, how did they do for you?

[Worth1]

I haven't figured out a way to cook and eat the pads as of yet.
Nasty slimy tart tasting things.
Cook like green beans my eye.
The fruit is another story and makes good jelly but loaded with seeds and pesky thorns.

[ilex]

Many opuntia pads have terrible taste, they are more a survival food. Some varieties are very good, like green beans. There's more potential in fruits, which can be amazing.

The best fruit I've ever tasted was a echinocereus. Just amazing.

Don't forget agave, some can be very good.

[Salsacharley]

I don't know about eating them, but here's some prickly pear wine I have going. Sorry its sideways.

[Worth1]

You'll be sideways after you get through drinking it.
Worth

The fresh prickly pear pads I've found in stores are great if you cut them in strips and stir fry them with chicken and other vegetables. They taste kind of like green peppers in stir fry, but with more substance, and they feel pretty healthy. Don't try that with canned or pickled cactus pads, though. It's not the same at all.

I tried blended up fresh cactus pads in salsa, but that that didn't taste so great. They might be fine in chili, though, in small amounts, by the taste. I've never tried that, however.