Recently, the distribution of velocity dispersion as far as 400kpc around redisolated galaxies was derived from statistical studies of satellites in theSDSS (Klypin & Prada 2009). This could help to constrain dark matter models atintermediate scales. We compare the predictions of different DM distributions,LCDM with NFW or cored profiles, and also modified gravity models, withobservations. It is shown how the freedom in the various parameters (radialdistribution of satellites, velocity anisotropy, external field effect),prevents to disentangle the models, which all can give pretty good fits to thedata. In all cases, realistic radial variations of velocity anisotropy are usedfor the satellites, and a constant stellar-mass to light ratio for the hostgalaxies.
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