veneers vs crowns

Hi,

I have a few questions about veneers and crowns that maybe some of you might have some insight into!

I got veneers on my front top six teeth about 20 years ago and all but one, which broke off, is in great shape however there is staining around the gum line of a few of them. I need to get the one that broke off replaced and would like to replace the others so that they all look good.

The front two original teeth were badly chipped and traumatized and both have root canals. The other four were healthy teeth which were prepped and had veneers applied to them to match the front two.

I am in a new city, San Francisco, and have to go to a new dentist and went today and they pushed very hard for all crowns on the front six teeth. I said that I just wanted the veneers replaced and they said that the veneers could break off. I also asked about just doing crowns on the front two and veneers on the other four and they said that I probably wouldn't be happy with the look of the result.

So, I'm left with some questions:

Why are they pushing so hard for crowns? Do they make more money with crowns or is it really in my best interest? Are crowns easier for them to do?

Seems like my veneers with the exception of one of them treated me well for the past 20 years. Why not just replace the veneers?

From my limited research, it seems like mixing crowns and veneers should not be a problem aesthetically. So, if it's a problem for them, maybe I should find some one with more experience?

I'm thinking I will get a second opinion and probably don't want to push for getting veneers from a dentist who insists its a mistake. Anyone have thoughts about my situation? Have I supplied enough info? Know a good cosmetic dentist in San Francisco that is in favor of veneers?

Thanks!