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We test and compare coasting cosmological models with curvature parameters k={1,0,+1} in H20c2 units and the flat ΛCDM model by fitting them to cosmic chronometers (CC), the Pantheon+ sample of type Ia supernovae (SNe), and standardized quasars (QSOs). We used the emcee code for fitting CC data, a custom Markov Chain Monte Carlo implementation for SNe and QSOs, and Anderson-Darling tests for normality on normalized residuals for model comparison. Best-fit parameters are presented, constrained by data within redshift ranges z2 for CCs, z2.3 for SNe, and z7.54 for QSOs. Coasting models, particularly the flat coasting model, are generally favored over the flat ΛCDM model. The overfitting of the flat ΛCDM model to Pantheon+ SNe and the large intrinsic scatter in QSO data suggest a need to refine error estimates in these datasets. We also highlight the seemingly fine-tuned nature of either the CC data or Ωm,0 in the flat ΛCDM model to an H1=H0 coincidence when fitting H(z)=H1z+H0, a natural feature of coasting models.

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