Even though I'm a republican I think it is better for the country to have at least one of the house,senate or president in the opposite parties hand.
The big reason is spending. With only one party for the house,senate and president all kinds of big spending packages get passed. I remember from one of the debates that Bush hasn't vetoed a single spending bill. This is bad in my mind because I want a smaller goverment.
With only one party they tend to spend spend spend.