Magnetic refrigeration using the adiabatic magnetization of paramagnetic materials was the first method to achieve temperatures below 1 K back in 1933. This method is still used in solid-state physics to achieve very low temperatures, although currently liquid helium is more used as a coolant in the region close to 1K. However, there are several reasons to revive magnetic refrigeration, which remains the preferred method for space applications. In particular, there are new ideas how to improve magnetic refrigerants by using cooperative effects.  After the discovery of new Yb-based intermetallic compounds applicable to adiabatic magnetic refrigeration at T<1K, the need arises to find some comparative criteria in order to select among different compounds the most indicated for different specific applications, like e.g. laboratory cooling processes or satellite devises thermal stabilization. Once recognized the conditions required for each type of application, alternative criteria for choosing the most appropriated system can be proposed depending on the different thermodynamic behaviors observed in these materials. Magnetothermal properties of those properties are analyzed according to the nature of their respective ground states.