I doubt anyone in this forum has ever touched a natural pearl that isn't baroque (misshapen). Boutiques such as Yvel specialize in natural baroque pearls.
Natural pearls are exceedingly rare and priced accordingly. And they don't look different to the naked eye. Experts can only tell the difference by use of an x-ray machine. I doubt any pearl you'll see on the market is natural, so unless you are looking at a budget of tens of thousands, you'll only have access to cultured pearls.
You've brought up a good point. Does anyone in this forum own a strand of quality round natural pearls? If you do, please, photos!