  For dynamical dark energy cosmologies we carry out a series of N-body
gravitational simulations, achieving percent level accuracy in the relative
mass power spectra at any redshift. Such accuracy in the power spectrum is
necessary for next generation cosmological mass probes. Our matching procedure
reproduces the CMB distance to last scattering and delivers subpercent level
power spectra at z=0 and z~3. We discuss the physical implications for probing
dark energy with surveys of large scale structure.
