I think the aluminum ones were a product of the crazy mtb peak in the early to mid 90's. The were lighter and could be made in all those obnoxious anodized colors.
My experience has been that they break and strip much easier.
Any time I hear a conversation about building strong wheels it always includes the use of brass nipples.
Hand built, (36) 14G spokes, 3 cross and brass nipples = one tough wheel