I've never tried canned crickets, but I doubt my leo would eat them, as she doesn't seem interested in things that aren't moving. Even waxworms have to be squirming a bit or she's typically not interested. I suppose it might be possible to train leos to eat dead prey similarly to getting snakes to eat frozen/thawed rodents, if you really wanted to work at it.
As far as the crickets vs worms in a dish issue goes, you'll get lots of opinions. My take on it is that crickets are the best staple, simply because they do run around. This has two distinct benefits over worms in a dish. First, it causes your leo to get at least a little bit of exercise chasing its dinner. Second, I think that chase is psychologically beneficial to the leo. They're predators, and hunting is part of their nature. Walking up to a dish and chowing down, while they'll do it, seems like it would train them to be lazy.
Anyway, that's my 2 cents on the subject, I'm sure others will provide contrasting opinions, and you can decide what is best for you and your geckos based on your evaluation of what all of us say.
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0.1 Albino Leopard Gecko - Tigger
0.1 Crested Gecko - Pooh-Bear