  The disordered microphases that develop in the high-temperature phase of
systems with competing short-range attractive and long-range repulsive (SALR)
interactions result in a rich array of distinct morphologies, such as cluster,
void cluster and percolated (gel-like) fluids. These different structural
regimes exhibit complex relaxation dynamics with significant relaxation
heterogeneity and slowdown. The overall relationship between structure and
configurational sampling schemes, however, remains largely uncharted. In this
article, the disordered microphases of a schematic SALR model are thoroughly
characterized, and structural relaxation functions adapted to each regime are
devised. The sampling efficiency of various advanced Monte Carlo (MC) sampling
schemes--Virtual-Move (VMMC), Aggregation-Volume-Bias (AVBMC) and Event-Chain
(ECMC)--is then assessed. A combination of VMMC and AVBMC is found to be
computationally most efficient for cluster fluids and ECMC to become relatively
more efficient as density increases. These results offer a complete description
of the equilibrium disordered phase of a simple microphase former as well as
dynamical benchmarks for other sampling schemes.
