Westin Savannah Harbor and RC Reynold Plantation
I have been to both properties numerous times. I was married at the Westin in Savannah and have celebrated my last two anniversaries at the Ritz. Ritz has far superior service and the spa is first rate. The golf choices at the Ritz are far superior to the Westin too. For relaxation and service go with the Ritz - I have stayed on the Club level, which is nice but certainly not the best Club in the RC chain.
On the other hand, I love the city of Savannah. The food options in downtown Savannah are far superior to anything you will find in Reynolds Plantation. The food at the Ritz is fine, but it's in a rural seting and there is not a lot off property. Savannah has great food, nightlife, and entertainment. If you like architecture, history, and shopping, Savannah is a great destination.
In summary, the Ritz is a far superior hotel, but Savannah might be a more interesting destination. It all depends on what you are looking for in a weekend getaway. I would be happy to answer any specific questions you have about the properties.