Of course it's a success, even not halting it but just slowing it down is a success to some extent....
I'm just using Revita shampoo (And Saw Palmetto, but it's the crap cheap dried stuff which I don't think is having any effect, I'm just taking it to use the bottle up). 3-4 weeks and I'm 90% certain I'm shedding less hairs than before. My hair doesn't look any better (It wouldn't in 3-4 weeks whether any meds were working or not) but the shampoo makes it feel and look better cosmetically (Nice and soft lol). And it's a lot nicer seeing fewer hairs come out.
I'm planning on giving it a few months (My hair loss isn't too bad and not aggressive) and if things get worse (It's not a case of 'if things don't get better, I'm perfectly happy just maintaining) I'll consider propecia.