Would you rather buy a foal out of a mare that is a proven producer or a mare that is a money earner?

With foal prices, I am genuinely curious what others would prefer or what would be considered more marketable. For me, I think I would rather take my chances on a mare that has been proven to produce money earners vs one that has not but has earned money herself.

Proven producer all day long.  There has been lots of perfomers that haven't produced. 

Abso Dang Lutely

Same argument can be used for stallions

Proven producer but both would be best option.