Hi!
Flicker will be as consistent as the gimmick you use to accomplish it. Questions? E-mail me.
Also, certain lighting will effect it... the Flicker doesn't look as good under flourescent lighting.
Google Flicker and my name and you'll find a TON of posts on the internet about Flicker's impact... or you could just email Justin Miller or Sean Fields, I think they're both members here.
Keep in mind, Flicker is a principal, not a sleight... which makes it easy, effective, angle-proof, and direct. No misdirection, knuckle busting, set-up (ok... VERY little set up), "gimmicks", or experience required. For what it is (a new principal, and a brand new card plot), it's well under-priced.