Toni - A successful advisor will have multiple satisfied clients, and will not hesitate to provide you references if you ask.
I've found it's generally a matter of expectations. Quality advisors are generally careful about which clients they accept. A client chasing `performance' is not one that will be happy with any advisor for very long; a disappointment is bound to happen. Likewise, a client seeking a long term prudent and disciplined investment process operating according to a plan is likely to be disappointed if s/he has an advisor who's always coming up with a new investment idea.
When the client and advisor are 'in synch', the odds of disappointment go down dramatically. I think the referral factor is one component - remember, even Bernie Madoff had glowing referrals and all from people chasing perfomance - but, being aligned on process may be just as important.