I didn't do too much research on those towns.I heard there is discussion on plan to extend NY subway to Secaucus. if the plan passed, the houses with walking distance to stations will be demanded, but I don't have the patience to hold lose now and wait for the bright future. NJ has the highest property tax, if you can not be sure your property will be rented out within a couple of month, you loose hundreds and thousands each month.
BTW, all my thoughts about JC is based on web search or talking with friends, I only visited newport a couple of time and drive too far on 280 then got lost in JC once :D).