What else are you going to do... if wearing for a few commutes highlights problems then you'll have to deal with the pain or bow out of the audax. Either way you'll have worn the bibs and so can't return them.
I am of course assuming you don't already have some bibs you can wear, in which case wear those...
I have some shorts, that have done sterling service, but are a bit knackered and I could do with something a bit less tired. I think I might go and get a pair and see how they go. I can take my old ones along as spares...
What else are you going to do... if wearing for a few commutes highlights problems then you'll have to deal with the pain or bow out of the audax. Either way you'll have worn the bibs and so can't return them.
I am of course assuming you don't already have some bibs you can wear, in which case wear those...