Outdoor Light V. Studio Light for Artistic Portraiture

[pavona]

Greetings all!!
I am trying to find my niche in artistic portraiture, but want to know your thoughts on natural v. flash lighting.
I need to buy a studio setup so that I can do indoor shots when necessary, but honestly, I like natural lighting better.....which typically looks better?
Which *is* better?
Also, any flash setup suggestions??

Thanks!!