The FLIR E4 will not directly drive virtual reality glasses as it does not have a composite or RGB video output. USB video stream only, via a computer. You could use a VGA virtual reality headset connected to the VGA output of a notebook computer that was connected to the camera. Messy but workable.
Lens angle of view is 45 degrees. Work out what your 42mm night-vision sight angle of view is for comparison.
45 Degrees is pretty wide angle and plenty good enough for foot navigation. It is not a 'zoomed' view. 9Hz refresh is fine for foot navigation but not really good enough for first person view flying of a radio controlled model. Fire fighters use cameras with this angle of view for searching smoke filled rooms. The refresh rate of their cameras is higher, but this is not a major issue in your case. The IRIS fire camera actually had the thermal camera on the side if the fire fighters helmet to provide the same directional view as the eyes. A chest mounted camera would disorientate you somewhat.
Thermal cameras only show a differential in temperature, so whether the camera will enable you to see enough to navigate in the dark is dependant upon the temperature profile of what is around you. Take a look on Youtube for examples of thermal camera use at night for hunting.
A thermal camera will show you wildlife that a night vision image intensifier may miss due to natural camouflage. That is why thermal cameras are excellent in warfare and in some cases restricted export items.
Night vision using a quality image intensifier, with or without an IR illuminator, can be highly effective depending upon the ambient light level and range required. Military pilots use 'Hot Gen3' star light image intensifiers to fly the aircraft, and thermal cameras to hunt for targets. The two needs are somewhat different.
By all means buy yourself a toy to play with if you can afford it, but no one else can make this decision for you or will try to persuade you one way or the other. Do some browsing on youtube to get a feel for what a thermal camera can do for you. The situation with improvements is presently unchanged with no sign of new firmware as of builds of 25 Nov. You will not find a better value thermal camera on the market at this point in time, or likely for some time ahead.
Take a look here:
http://www.optimumenergy.com/top-five-myths-of-thermal-night-vision/http://www.policemag.com/channel/technology/articles/2013/03/20-things-you-need-to-know-about-night-vision.aspx