Just have a look at the ferry fee (both ways or to Victoria and then over to Vancouver) for your TT and it will be an easy decision!!
AND getting the TT back in to the USA can be easy - time consuming - or frightening - depending on the breakfast the inspector had that morning and his relationship with his wife / girlfriend.
Honestly - we have had 3 trips with our 'A' into Canada / Alaska and the entry into Canada has always been easy and the re-entry to the US easy twice and once a complete terror. (I think they must have thought this old couple were bringing something 'interesting' back home!!)