The best power supply is the one that works best for the intended application which you fail to mention. Additionally SMPS supplies have transformers just like linear have transformers. SMPS means Switched Mode Power Supply so what exactly are you asking? With or without regulation? Regulation being the only difference I see above with two SMPS supplies. What is the app and what is the allowable ripple?
The application determines which supply type would be best. There are considerations like cost included in the decision making process.
The practice of following the SMPS with a linear P/S is to reduce ripple in the output and increase transient response speed. If you are just driving a relay, it won't need that added performance so it's a waste of money.