If you are dedicated to Pokemon and like nostalgia, I would go for the Eevee tamagotchi first because they're getting quite limited. Also, in comparison with Gudetama version, Eevee version slightly has more features which is 2 mini games, cleaning/hairball and feeding. Gudetama only has the chopstick predator, 1 mini game and feeding. (Then again, Gudetama version is mostly about killing your pet to see their final cooked form.) Regardless, nano tamagotchis are great for busy people or people multi-tasking with other tamagotchis.

However, if you are not dedicated for Pokemon or have limited spending, go for the Meets instead. But, having rechargeable NiMH batteries would be very essential for them since they generally last for 2 weeks. As for glitches, it's only some unlucky people who encountered them that are complaining. (For me, I've been having a solid experience along with the app.)