Comfort from best to worst, IMHO

Cycling bibs
Cycling shorts
Liner only? (I really don't think these should be worn by themselves)
Regular workout shorts, commando (be prepared for flapping around of all things fabric and non-fabric)
Liner + workout shorts
EDIT: Insert cycling shorts + workout shorts here (I can't see how this could be more comfortable than wearing a liner, which is designed to be worn under other clothing)
Any kind of underwear under any other kind of clothing
Full commando? (theoretical, more data required for meaningful comparison)
Non-exercise clothing e.g. jeans, commando

Basically, the fewer layers of fabric excluding chamois padding between yourself and the saddle, the better.