I've tried a ton of VB stuff over the years due to the fact my fingers and toes are like rabbit/elephant ears (more surface area than mass) and VB's are a guaranteed way to keep my toes warm. I've never found them to work with my hands but some people have had luck using grocery store dishwashing gloves. Forget the nitrile surgical gloves. I have found they make matters worse. I've worked cold water fisheries for the past few years in AK and CO so I'm an expert at having perpetual cold hands. The only thing I have found to date that will keep my hands warm in any temps are black diamond's mercury mitts
http://www.bdel.com/gear/mercury_mitt.php or hothands warming packets (but I'm too cheap to use them except for emergencies like winter fishing). You can use the shell or the insert of the BD's separate from each other depending on the situation. I have the mitts in my pack every time I go out in the winter.
As for feet, I will use golite VB socks over my normal winter socks (not layering over a liner and oversock like recommended) if need be but, as eric stated, the only problem is them slipping around after walking a while. But if I need to keep my feet warm, nothing else can give me the guaranteed results as VB socks can. I would rather have warm damp feet if I have a layer of wool around them and VB socks over than numb toes.
Can't use anything on my core because I sweat way too much. But, two gore-tex jackets work as well as VB clothing for your core.
If you want to experiment on the cheap, use bread bags for your feet, dishwashing gloves for your hands (in this case put an insulative layer over, and a poor man's poncho (hefty trash bag) for your core underneath your other layers.
Check out
www.warmlite.com http://www.warmlite.com/vb_shirt.htm#anchor70781 for info about VB clothing but, keep in mind, they're naturalists (nudists).
I am now a proponent of climate conditioning to extend my cold comfort range in my hands and feet. I've heard about this for years, but doubted it's validity until recently. For your feet, go barefoot as much as possible in the winter while around your house (it helps if you keep your house "cold" in the winter) and limit your glove use as much as possible. Rewarm if necessary with your own skin contact and/or your breath.
To really take this to the extreme, make a bowl (big enough for both your hands and/or feet) full of ice water and cycle your hands/feet in and out of it. Do this as often/as long as you want but don't get frostbite.
Believe me, it sucks, but it works and makes your hands and feet much more resilient to extended cold weather trauma.
Remember, "wicking" is a marketing term for "evaporative cooling".
Good luck and I hope this helps.
BTW,
http://www.wildernessexchangeunlimited.com/ is where I bought the mitts and VB socks.
