Crowns don't have any special odor or taste to them, and once in place for a few days you really shouldn't notice they are there. As far as bad breath or halitosis, crowns won't cause it but not keeping them clean will. If plaque is allowed to build up on the crowns then there could be a bad taste or odor (or decay that can cause a crown to fail). The fit of a crown is more the result of the ability and care taken by the dentist and lab than of one type of crown over the other.
There are many different types of crowns, these could be all gold, or porcelain fused to metal, or all ceramic. There is really no one best material for all situations. I would be very cautious of crowns at the low end of the price range for your area. Often these are porcelain fused to metal crowns which contain nickel instead of a precious metal such as gold. The issue with nickel is that many people, particularly women, are allergic to it. This increases the chances of problems later on. These types of crowns are also frequently made offshore for a very low cost and with questionable quality.