Hamsters are great and easy to take care of, but personally I don't like them as they don't interact with you. I feel that that's a critical requirement for a pet.
Never had a guinea pig, but they supposedly smell. Otherwise they seem pretty perfect.
I currently have a rabbit, and have had multiples in the past. They're fantastic, but really need a lot of space to run around in. So unless you toilet train them, it'll quickly become annoying.
I've had quail recommended to me, they sound awesome but I still need to figure out their dust bath needs. Plus they lay delicious eggs
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