I've bred guinea pigs for 8 years now so the "responsibility" won't be new to me and I'm still with Souffle on the temperament thing, I never bred the best show quality guinea pig if it's nature was appauling, it's just not worth doing because (oddly enough) those personality traits DO follow through.
And just "for the record" I would never
contemplate breeding a pet shop hamster and CERTAINLY NOT a rescue, I think I mentioned that before but I wanted to reinforce the point, there are definiate NO NO's and they are 2 of them
My female syrian Mildred is a rescue so that rules her out, plus she's over a year old. And she's so fabulous I don't want to change her at all so wouldn't want to breed from her anyway.
Does littering a hammie sometimes "ruin" it personality wise? With guinea pigs sometimes littering them was the making of them but in other cases it went completley the other way
I guess at the end of the day it's all down to knowing your animals and trusting that YOU know what's best for them