I have a vHoldr and Go Pro HD. My vHoldr is not the HD. I bought it last year before they came out with the HD. As far as ease of use, the vHldr is very easy to set up and use on your helmet. The laser sights are invaluable.
The Go Pro HD has amazing picture quality. Because I don't have the vHldr HD, I can't compare. But it is far superior to the old vHldr. So much so, that I am going to sell my vHldr.
A couple of things I love about the Go Pro are it can hold up to a 32 gig memory card. It writes to an mp4 file (the vHldr writes to an avi file). You can instantly watch your Go Pro video on a TV monitor. Something the guys spend all night doing after a great day of ditch banging and carving!
I have had NO problems with the Go Pro. It is very user friendly and works flawlessly. Now if they only made it with laser sights!