Our guy LOVES his silkies...
A large silkie is about the same as 3 crickets...if that helps you any. Our guy is 11 months old and will chow down about 10 large silkies a day.
Silkies have a lot more moisture than crickets--so you will notice their poo being more watery...
Silkies make a great staple, however we decided that it was best to give our guy a varied diet. Besides the veggies, he gets silkies, crickets, occasional superworms and occasional wild caught bugs (we live in the country and our land has not been treated with chemicals).
I've been using californiasilkworms.com as my silkie supplier--very good service so far. Please let us know if you find a better supplier...
Also if you get 200 large silkies make sure you purchase enough chow--they eat a lot!
Draksomom