I have the SR1911 commander, the STI Spartan IV and The STI Spartan V. They are all great guns and I have had zero issues with any of them. You cant go wrong with either one. I think it is personal preference whether you like the stainless look of the Ruger or the parkarized surface of the Spartan. The Spartan also has front serrations and a better front sight than the Ruger.
Not picking on you, a lot of other people have posted it as well. I must have got the only crap Ruger SR1911 commander out there. Between that and the LC9 my experience with Ruger is not so good.