1. A method for execution by one or more processing modules of one or more computing devices of a dispersed storage network (DSN), the method comprises: determining that a plurality of sets of encoded data slices is to be stored in a set of storage units of the DSN, wherein a data object is dispersed storage error encoded to produce the plurality of sets of encoded data slices and wherein a storage unit of the set of storage units includes a plurality of memory devices that includes one or more solid state memory devices and disk drive memory devices; identifying one or more devices of the DSN that will potentially issue a read request for at least a portion of the data object; determining one or more sets of transmission times between the one or more devices and the set of storage units; and determining a storage strategy for storing the plurality of sets of encoded data slices in the set of storage units based on the one or more sets of transmission times and the pluralities of memory devices of the set of storage units, wherein the storage strategy indicates whether storage units of the set of storage units are to store encoded data slices of the plurality of sets of encoded data slices in a solid state memory device of the one or more solid state memory devices or in one of the disk drive memory devices such that, from set of encoded data slices to set of encoded data slices of the plurality of sets of encoded data slices, at least a threshold number of encoded data slices are retrievable with comparable read response times.