Should I go with 6" wide rim?

I want to install 215/55/R16 sized tires on my 2003 Toyota Matrix.

What are the disadvantages, if any, of using rims that are 6" wide instead of 6.5" wide?

Many thanks for advice.

The tire will tend to arch and ride in the center of the tread, causing more wear in the center as well as more sensitivity to wind and ruts in the road.

However, these affects are pretty small.