1) Do fighters get to choose the gloves they want to wear or do they have to agree on it or is it written when they sign their fights or whatever. how does it work? 2) There are certain gloves that protect your hands better for the fighters with bad hands (Mayweather, Calzaghe, Malignaggi i also think Morales had bad hands too) These guys usually go with Winning gloves or Grant or Everlast in the case of Malignaggi. Just because it protects their hands better, does it have any effect on their punching power? Like if they actually wear reyes they will hurt their opponent more? I have never understood that 100% Can someone clarify this for me?
Sorry, it does change a lot of things. That's why it's often negociated. But each brand has many choices. But in general, punchers prefers Reyes. If you take Lucian Bute, he fought 5 times without Reyes gloves: 4 decisions, one ko. With the Reyes gloves, 17 fights, 17 ko's. If the glove protect you hand, it's because the impact on the opponent jaw is lesser.
Usually the power is about the same, i think the biggest difference in gloves is the chances to cut your opponent. But this is my personal theory since the difference I've felt with less padding in the gloves is a better feel of the fist, but over all if the gloves weigh the same the impact is similar and the punches are a little slower than with lighter gloves which also takes away from the power.