I'm a Canadian and I have used CaVirtex for a while. As far as the Canadian market is concerned, they're a high volume exchange and more or less had a corner on the Canadian market because they got all their ducks in a row (KYC and working w/ major Canadian banks etc.) and they remain reliable (for a while they were the only game in town for Canadians), but Vault of Satoshi could very well unseat them as top dog now that VoS is moving forward in the USA state by state, plus VoS has transparent proof of solvency.
CaVirtex charges such exorbitant fees that I kinda wanted to invest at one point if even to reap back a little of those fees and high prices I've paid into them. They MUST be making money, but Vault of Satoshi could become the real mammoth here.
Proof of solvency is cute, but VoS is still a centralized exchange, holding all the bitcoins for the trades, and is thus just as vulnerable as Mt.Gox was. If suddenly the proof of solvency shows that VoS is insolvent, what good does it do for all those that are already using it?
The fact that VoS is multinational is not necessarily a good thing either.
As for Cavirtex, you can calculate what the lion's share of the money they make is by simply multiplying their $80 million total transaction amount by the 3% fees they make (1.5% from the seller, 1.5% from the buyer) and see that they have made $2.4 million in total fees in their businesse's lifetime. It's not that much for a business of 20 employees. Shareholders won't get many dividends with that kind of money. Cavirtex need to grow, and it looks like they are trying to do it very carefully.