Re: Root Canal Questions - 1st one kind of urgent
If cost were not an issue, I would use the best quality metal I could get - the gold or a gold alloy is a very good crown. Lots of people want porcelain now, but they are just too weak to last any length of time. Maybe 5 years on a molar. The metal is far stronger and really worth it as it may very well last you 15 years or more. When you get in to lower grade metals, they are not quite as strong and they have more of an incidence of causing problems with your gums, which can react negatively to metals. This is greatly reduced with the gold. I think between the two, gold is the way to go.
As for cracking the tooth, I have never heard of a root canaled tooth cracking during the crowning process, though it is a possibility. I would not worry about it though. As long as your dentist is a good restorative dentist, your tooth will not have a great deal of force on it during the process. The tooth will be growned down gently and the a mold taken, and a temp put on. If the dentist and lab do a good job and you do not lose your temp the crown should go on very very easily and that will be the end of it. It takes a long time for a relatively healthy tooth to become brittle enough to break while getting crowned.
And for what dentist, if you like your dentist and plan on continuing using him, I would just wait. You should be fine and your dentist and you have a relationship you can't get with a dentist you just see once or twice to get a crown.