I disagree, Gingerbread version 2.3 is officially available for Samsung Galaxy Mini Pop S5570. Gingerbread is a far better firmware even for low end 600 MHz processor based smartphones when compared to Froyo.
You will not lose any data if you update it officially using Samsung Kies software. However, if you decide to manually update it using the Odin software, you would need to backup your data before you flash your device. Backing up all your contacts, sms, pictures, videos and songs is extremely easy and you can always restore them once you have the updated firmware running.
The Gingerbread firmware available for this device is officially released by Samsung and will not have any bugs. However, if you download a third-party firmware and flash it, you may encounter bugs. I suggest updating and running the latest firmware available for your device.