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Self-acting gas bearings are a popular solution for small scale turbomachinery. Many designs have been studied, and among those, the following three are very diffused and promising: foil bearings (FBs), herringbone-grooved bearings (HGBs), and tilting pad bearings (TPBs). Despite the many studies investigating these architectures individually, a direct benchmark between them is still absent. This paper proposes a side-by-side comparison of the three concepts specialized to one common application: a 14 mm rotor with a nominal speed of 150 kRPM. To achieve this, a numerical model was implemented, using a 2-D point mass rotor. Performance metrics were then calculated: static equilibrium positions and fluid film height, Campbell diagrams, logarithmic decrements, friction losses, and the full orbit response under a selected unbalance. The FB exhibits the largest fluid film heights and lowest losses, but higher rotor eccentricities; the HGB shows minimal eccentricities with higher losses; and the TPB provides superior dynamic stability, also at the expense of higher losses.