Ahh...no wonder you are able to use such low shutter speeds. I should really consider at least using a monopod.
So - question on the Vanguards: do they offer some type of lifetime guarantee, or did you buy a warranty that covers them?
My tripods had a standard 2 year warranty, but if you register with Vanguard they will add another six years without cost, which I did. One was four years old and the other two. On both some of the legs would not stay spread. I sent one in to be fixed, but it did the same thing a week after it was returned. I called and they said it was an old style design that would wear out with heavy use (like with me every day) and could not be fixed. They told me to send both tripods back in and they would replace with new upgraded versions at no cost.