In #OracleSolaris 11.4.78, the iostat command now accepts fnmatch(7)-style patterns for matching disk device names, such as "iostat -xnb c1t[0-2]d\* 1 1"" (the \ is to avoid your shell trying to expand by itself).
Also, the new option '-b' to iostat displays backend statistics for virtual devices assigned to guests (Kernel Zones or LDom guests).