They are hated and despised by their main clients, the used car...

They are hated and despised by their main clients, the used car dealer network that advertisers with them. This is not a good thing for their long term prospects. Yes monopoly for now but their customers are getting smarter and withholding from advertising large portions of their inventories and instead using " generic type" advertising to keep their own costs down.
I don't know of too many motor dealers that are on the "per click" charge basis but rather on the $100 per month per car and used sporadically.

In addition to this, advertisers are getting smarter and are working their web pages in conjunction with SEO and google keywords in such a way that they are pitching directly to the consumer and in many ways bypassing CRZ entirely.

CRZ have tried to branch out into other avenues such as with their Quicksales.com, but this turned out to be a flop for them. Just like the other players can't threaten them in the car market advertising game, they in turn will not be able to make inroads into other advertising markets dominated by more established players. Taking into account this along with other factors, I can't see much growth left in them.

When investment banks start putting BUY recommendations on already over valued stock then this is definitely a SELL