For the Sniper it's really useless. But for a skilled tank, shazam. I used to run a speed support before the Hurt/Heal nerf.
Gold speed is a blast on the tank, but running it means you sacrifice rof/ armor / or skill recovery. I roll it 90% of the time in pubs, but in higher level games I'm reduced to a supporting role of spamming a ranged blind, clearing bot waves, building shave ice, and crowd controlling juiced pros. Higher level play would probably allow you to play conservatively with a non speed build, and allow your team mates to call out speed drops for your heavier classes, meaning you get the benefit of a high survivability rof skill tank, a streak, AND gold speed. But in pubs, gold speed is amazing.
Speed is best on classes with high destruction and slow movement. Support with any speed endorsement makes the shotgun a nightmare. You can out shoot a gunner if their gun hasn't been warmed up. Tank is also excellent with gold as you can get around faster and get in close with the jet gun. Sniper doesn't need speed. Assault makes things a little more easier to avoid damage. Gunner can benefit this along with reload if you want a good hit and move gunner. Assassin this makes walking backwards easy to escape many hectic moments. If you can manage to get 3 kills in a row then there is no need for speed. But overkill makes things even better. If you can out shoot some and stay behind them you have easy kills.
Ya. If you're rolling around in a pub solo dolo speed is amazing. But playing against competent players with Armor/RoF you'll have to be a little more dependent on the team then yourself. Sniper doesn't need speed because he has range, and flak for crowd control. Assault, I used to use gold speed with assault. It was awesome, using hit tactics and flanking with bomb jumps and etc. But people got better so I had to switch to a different build.
I have a sniper build with gould speed, his sole purpose is melee's/heck yeah's/flak But speed imo is ok on assassin, but that bronze endorsement is better off being something else, seeing as her mobility is insane
