I just set up my PVS14 I won in a raffle. I opted for a bump helmet instead of the skull cap. Too many online comments about the skull cap and how uncomfortable it is. I also went with the same as Eben is selling, simply for the cost. Wilcox is higher dollar and more high speed and low drag upper tier stuff. Other stuff to consider is a battery pack or pouch (depending on your unit) and how to mount it to counterweight the NOD. With the helmet, it is easy, not sure about the skull cap. Also ear pro, what are you going to need to wear them with the skull cap. On the helmet, you can attach the ear pro muffs directly to the helmet withan adaptor, so you have everything as a single unit. Oh yeah, start looking for two infrared devices - a decent IR laser illuminator to be mounted on the rifle, and a decent NVG compatible optic. My laser is the Holusun LS 221. Steiner and several other brands are available for $400+ more than the Holosun. Most receommendations for the optics ware for the EoTech EXPS3 with the EXPS3-4 version being the best (500 yard BDC reticle) and NOD compatable. I had a Trijicon TriPower laying around and found that the tritium illumination was sufficient for the PVS14 to see. so save a bunch by using that.
In reality, everthing I needed turned out to be a buy and try method. I would buy what I thought I needed/wanted, try it out and then go with something that worked better. Of course I do the same with buiding and setting up a rifle. That's why I have trays of spare parts in my shop.