OMP overalls - any good?

[shirt]

looking at these ones:

http://www.demon-tweeks.co.uk/motorsport/mechanics...

i need decent black overalls to outfit our amateur race team. we race in high 20s/low 30s so the lightweight would be appreciated but i am concered that 160g/m is about the weight of a cotton shirt, which makes me thing they wouldn;t stand up to much.

anyone got a pair and rate them? or what do you recommend?