I'm not sure what TSX listed trusts my friend has. I know that Vermillion is one that he has often recommended.
Neil George only recommends ERF on the NYSE. The other Canroys that he recommends are: Vermillion, NAL, ARC, & Shiningbank. All can be had thru pink sheets. When I had a TSX listed stock in Scottrade, it was listed with a "-un.ca." The pink sheet ID just seemed to get the broker confused.
Prices should be very similar except for a small amount for arbitrage between the two .75% give or take. US is probably more liquid and hence lest costly for most. Over time they will do the same.Slightly different holdays as well. Unless of course you meant TSX only listed, which with the exception of COS are all much smaller companies. As they get larger they will typically dual list. Smaller generally means more subject to panics. The discontinuity that you saw last week was noise associated with the Thanksgiving holiday and the differing schedules. It should be washed out by now.
FYI COS is US listed on the pink sheets COSWF.PK I would suspect many others are.
personally, i try to stay away from the trusts that trade only on tsx, for a number of reasons, including liquidity and options trading. COS is about the only exception and it is, imo, overpriced right now, given the uncertainty of the economy.