I have a 33kg Vulcan on Iron Bark III which stows neatly under the bowsprit, but I did have to build a new set of rollers as the standard one is not robust enough for that anchor. The Vulcan holds well in a variety of bottoms, will generally work its way through kelp and resets reliably on a windshift. The one thing it will not hold in is in coarse glacial till such as is often behind the eyis in Iceland, but then I don't know of an anchor that will hold in that sort of bottom.
Before the Vulcan became available, I built a roller system that allowed a 60lb Manson Supreme with its rollbar to stow below the bowsprit on IB2. It was quite expensive in materials and took a bit of doing. Now the Vulcan is available, I would not bother.
I am lying to the Vulcan in Bantry Bay and it is blowing a gale with squalls to 50kts or more and the anchor has not budged (but it is a good mud bottom and not much sea finds its way into the nook where I am anchored). The Vulcan may not set quite as quickly as the SPADE but it is cheaper and more robust and its ultimate holding is probably as good. For my purposes.the Spade is too fragile. I had one on IB2 and had to abandon it after 4 years because it was corroded to the point where it was unreliable. The hollow shank is very strong as manufactured but has no margin for wastage. The unsealed lead in the tip resulted in rapid electrolysis in tropical water temperatures which badly weakened the anchor. For a vessel that always lies to its own gear (no marinas or moorings), I think the Vulcan is a better bet, especially in warm water.
There is nothing like an anchor debate to make sailors dogmatic, but I have used most of the generally available anchors and am firmly in favour of the new generation of sugar scoop anchors. I hope never to have to use a plow anchor again.
Cheers
Trevor
Iron Bark III, Glengarriff, Bantry Bay, Ireland