Roger,
If you go from Roche Harbor to Sidney (Port Sidney Marina) you can check in with Canada Customs, and then travel south inside the islands and around the corner to Victoria. This limits your exposure in Haro Str to weather and shipping. The tidal currents on the route from Cattle Pass to Victoria can kick up a lot of confused seas.
If you don't want to go into Sidney, I would still use this route, but turn left past Sidney Spit, and continue to Victoria and check into Customs there.
