The only way to get an answer to that is to try the disc and see if the detail on those roads has been added.

Major urban areas get upgraded at a pretty detailed level, while the fly-over counties where man and beast live alike get less attention.

Get one and try it. Maybe you can borrow the new data version (5) from a friend who has upgraded. Note that NAV systems in 2005 and newer RXs are Gen 4 NAV systems that use a different disc, so you have to use a disc for a Gen 2 or Gen 3 car. (Any RX up to and including 2004.)

If you bought your car new, it probably came with Data version 2.01, so if you have data version 3.01 you have already upgraded once. (Go to Menu and press DVD up in the right corner to see the data version of the DVD -- this is NOT the GEN designation of the Nav system but the data version of the map and POI data on the dvd. -- Ver 1.01 came with '02 cars, and ver 2.01 came out in 03-04. Ver 5.01 came out in Jan of '06.)

 

Were you able to find out if this disk (Navigation Update DVD 86271-53020 05.1) works with Gen 3 navigation system?