Did the dark energy always have a large Compton wavelength?

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Until now all well-studied dark energy models proposed have very large Compton wavelengths, λc > 100 Mpc at all time and hence show no clustering on small scales. Evidence against this would disfavour both ΛCDM and quintessence. We show however, that large λc is actually favoured by current CMB, LSS and SN1a data by comparing quintessence with a condensate scenario with the same background dynamics. The condensate scenario has a very small λc before making a transition to negative pressure and large λc and therefore exhibits a rich CMB phenomenology which roughly interpolates between ΛCDM and flat CDM models.