Lot’s of wrong on this thread.
Gravity is a force, and is very much dependent on mass – as per burnie’s equation. Of course, the acceleration that results from a force is also dependent on mass (a = F/m) , so in the absence of other forces, the resulting acceleration will be the same.
Of course there is another force – air resistance, and for “similar build” let’s assume they’re the same.
a = F / m
F = F(g) – F(a)
where F(g) = force of gravity = g * m
and F(a) = force due to air resistance which is independent of mass (for “similar build”)
This gives:
a = (g * m – F(a)) / m = g – F(a)/m
A higher mass reduces the impact of the air resistance, and so will accelerate faster.
EDIT – of course it’s not really g * m except on a vertical slope, it’s some fraction of it, but it makes no difference to the conclusion.