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We aim to study the temporal and spectral behaviour of four polar CVs fromthe infrared to X-ray regimes, refine our knowledge of the physical parametersof these systems at different accretion rates, and to search for a possibleexcess of soft X-ray photons.  We analysed four XMM X-ray observations of three of the sources, two of themdiscovered in SDSS, one in RASS. The X-ray data were complemented by opticalphotometry and spectroscopy and, for two sources, archival Swift observations.SDSSJ0328 was X-ray bright in two XMM and two Swift observations, and showstransitions from high and low accretion states over a few months. It has nostrong soft excess. We measured the magnetic field strength at the main pole tobe 39 MG, the inclination to be 45<i<77 deg, and we have refined the long-termephemeris. SDSSJ1333 was X-ray faint. We measured a faint phase X-ray flux andplasma temperature for this source, which spends almost all of its timeaccreting at a low level. Its inclination is less than about 76 degrees.1RXSJ1730 was X-ray bright in the XMM data. Its spectrum contained a modestsoft blackbody component, not luminous enough to be considered a strong softexcess. We inferred a magnetic field strength at the main pole of 20 to 25 MG,and that the inclination is less than 77 and probably less than 63 deg. V808Aur was faint in the Swift observation but there is still strong evidence forbright and faint phases in X-rays and perhaps in UV. Residual X-ray flux fromthe faint phase is hard to explain by thermal emission from the WD surface, orby accretion onto the other pole. We give a revised distance estimate of 250pc.  The three systems we could study in detail appear to be normal polars, withluminosity and magnetic field strength typical for this class of CV. None ofthese systems shows the strong soft excess thought commonplace in polars priorto the XMM era.

X-ray and optical observations of four polars