lorax - 12:38 pm on May 7, 2013 (gmt 0)
Welcome to WebmasterWorld Bootstrapper,
X-Cart is not THE best cart. There is no one cart that is the best solution. It really depends upon what you need for functionality and for your tolerance/desire for customization and control.
Re: WordPress eComm, yes there are several plugins/solutions. Ecommerce Templates, FoxyPress, GetShopped. More here [google.com].