I used the Newark Penn Station Airlink recently... I would not recommend it going to EWR in the afternoon. Traffic is very congested around the train station and it takes the bus at least 10 minutes longer to get away from the station as it ought to. Heavy demand also results in long queues and very crowded buses. Also, if you're not going to Terminal A, the loop-de-loop that the bus uses between terminals is maddening.

The 302 is intended for airport passengers, the local bus for employees and other locals. The 302 has luggage racks, the local bus does not, so luggage pretty much has to go in the aisle. This slows down the bus considerably at every stop when the bus is crowded, so I have no problem with NJ Transit enforcing the rule they have about passengers with lots of luggage on local buses. With the taxi to Manhattan costing about $45 with tip & tolls, I don't really care whether the bus costs $1 or $4.