Do not get those performance ultra shorts, talk about see thru, run 2 sizes to small, and super uncomfortable. Try the Voler for the price they are nice.
Bibs vs shorts. Bibs are hands down more comfortable than shorts. You have to try them to understand why. I was against them as well, once your in them and used to it, no comparison.
And the pad in the ultras is horrible foam type thing.
And as said above, there is no substitute for good shorts/bibs. Spend a little extra and get a better pair and you will not be disappointed. For the price try the voler. The PI is nice but the pad is a little odd. I like my assos and castelli but they are a bit higher.
No cheap shorts and you will be much happier. Bank on that.