I find Rocktape far better than KT tape. It stays on for days if needed. A roll is 12quid from sweatshop, compared to 20quid for KT tape from Sweatshop.
As to whether you believe in it, no harm in trying. I've used it as part of recovery from a shin splint, pes anserinus tendonitis, and some calf trouble. On balance, I think it has helped