I have been to both USMNT and Red Bulls (lord, how much I can't stand the name) matches in Harrison both from the city and from the burbs. From the City, basically take the PATH from WTC (about 20 minutes) to get there and its a 10 minute walk from the Harrison PATH station. Technically, its about a 15 minute walk from Newark's Penn Station for people who take NJ Transit; but, its rare to do as its Newark, though the route would take folks from two of the safest neighborhoods in Newark - the business district and upper Ironbound. With respect to driving, I usually park at the PATH station garage and walk over, again simple, and the immediate area around the Arena has become nice with new residences, hotels, and basic restaurants driven by the recently re-built PATH station. The challenge is that while the area immediately around the Arena has been built, the space in between the Arena neighborhood and the highways (I-280 and Route 21) has not. That space is not dangerous; but, its tricky to navigate, especially at night. The Arena itself is nice as its designed for soccer, so the sight lines are good and the roof keeps the sound in. Much better that NYCFC's use of Yankee Stadium. Simply stated, I think this biggest issue for Red Bulls is that its in Jersey and not NYC proper and that impacts people's perception of the team. The Red Bulls are also a bit nervous in that NYCFC has developed a training facility on the west side of the Hudson in Rockland County NY, which historically been considered Red Bull territory. The big question thus becomes where will NYCFC build its own stadium.
A shout out to the town of Harrison, its a small, tough, factory town of about 17,000 people with a lot of soccer heritage. It's high school, which has about 700 students, has won over 25 state (NJ) soccer titles. I think its a national record or something. Harrison High also has a really bitter soccer rival with next door Kearny High school (1,600 kdis), which is the hometown of Tony Meola and John Harkes.
The World Cup is an obsession in North Jersey cradle of American soccer