Choosing a Breeding Pair

Once a female has been chosen to breed, which criteria should I look for in a male to use for pollination? I know which strain I'd like to cross the female with, but I haven't as yet chosen a father. Is it best to just pick the fastest, healthiest growing male plant, or is there another way to tell which may carry the strongest genes.

same criteria... I look at everything from internode spacing, color to health...

I think I read somewhere that also look for smell by running hand on stalk... What smell u look for, I don't know :/