Is the Garmin National Parks software worth getting?

I use a Garmin 60CSx with the US TOPO map and the National Parks West Topo map. I load selected portions of these maps into my GPS before venturing off into the wilderness. If you're looking for trail information or plan to do some off trail hiking then the answer to your question, in my opinion, is yes. The biggest reason is detail. The NP Topo uses a 24K scale while the US Topo uses a 100K scale. Another reason is the NP Topo contains most of the NP trails while the US Topo shows just a few. However, a few of the trails are out of date. By out of date I mean the trail route may have changed since the maps were prepared. An example of this is the Twin Sisters trail in Rocky Mountain NP. The trialhead had to be changed because a private landowner closed access to his property. The new trailhead is in the back of the Lily Lake Visitor Center but the NP Topo map still shows the old route. I suggest you check any trail you'll be hiking using the lastest infomation on the web.