Like cooking clothes, it's very hard to see why anyone would invest in these, given how lackluster training mastery is. In particular, two of the three bonuses from training mastery - increased capture chance and increased horse exp - are so low that using the mastery clothes is ALWAYS the worse choice than using the free alternative you get from the reward tab, which gives much larger bonuses to capture chance and xp rate (and also gives +training exp and +horse skill exp to boot!). So there is literally no reason you would ever equip these clothes for actually riding or taming horses. In fact it actively gimps you, since it slows down your training SKILL advancement, which provides much more useful bonuses than what you get from mastery. This seems pretty stupid to say the least. So that means, like cooking mastery, the sole purpose of these clothes appears to be to wear when you are breeding (or smashing, lol) horses. It seems hard to believe PA really intentionally designed these to be used solely for the 1 second out of every several days you hit "breed." Not to mention that the bonus here is so low that it's hard to see it ever paying off your investment, particularly for manos. Does another 1-2% chance at getting a T8 really justify the investment of billions and all that time farming fragments? You'd probably come out better just doing more horse training to level your training skill, since again that provides much better bonuses. Like cooking clothes, these need a rework so they're not such a terrible investment choice. Either training mastery needs to give much better bonuses, or the clothes themselves need to have some other bonuses added to make them a better choice than the free alternative.