using fiberglass matting?

ive done 2 boxes,both using fiberglass matting in each layer.some people ive seen dont use it though,they just do coats of resin then bondo after that and it seems to work. i always thought you had to use the matting though.any thoughts or reccomendations.if i could eliminate the matting id love to,just dont wanna try it then have to start over.

Definatly stick with the mat or cloth on boxes......Resin just isnt strong enough by itself.....