Mature Metal discussion

Hello everyone - I’m trying to figure out which Jailbird size to get, but the feedback on cage length seems contradictory. Mature Metal advises:

The right measurement is taken when you are at your smallest, but NOT while “shriveled up”. Click to expand… However, according to PansyTart’s measuring method, point B says: You need to measure the cage length and internal diameter by compressing your shaft into a relatively short “bloodcock” shape. Click to expand… Does anyone have guidance on how to reconcile this seeming inconsistency? I’m concerned that if I go with MM’s recommendation, the cage might end up too long, leading to disappointment. Thanks ahead of time!