It’s not really about whether one is better than the other — it depends on the use case. KioskOwnerCap can be transferred to others, so the Mysten team created something called PersonalKiosk, which you can think of like a soulbound object.

Also, to ensure that an NFT is only sold to users who are using a PersonalKiosk, there’s a rule called personal_kiosk_rule.

You can read more details from the package here: https://github.com/MystenLabs/apps/blob/main/kiosk/sources/rules/personal_kiosk_rule.move

PersonalKioskCap offers a safer and more convenient way to manage your own kiosk. It essentially ties your control over a specific kiosk to your address, preventing accidental transfers or loss of the KioskOwnerCap object itself. This makes common operations simpler and much more secure, as you don't have to constantly pass around or worry about losing a transferable object just to interact with your own kiosk.