Chastity device reviews discussion

I’m considering buying a new steel chastity cage that doesn’t use a loose padlock, similar to the jail bird style models. It doesn’t have to be an original Jail Bird product; I just need some guidance on sizing—specifically, how much longer should it be when flaccid? Also, is it better to choose one with a urethral insert or go for a model where you can remove that part? Are the base arc ring designs good, or do they cause irritation against the scrotum? I’d appreciate responses including photos if possible.