I've been using my own speed hack for a while now and haven't had any issues, but I suppose YMMV.
The Sprint buff is 1966130 in memory and you can lock it with cheat engine for perma-sprint.
Additional buff slots are at memory address hex +C.
All of these buffs appear to be client-side only, unfortunately.
1966247 - Instant Cast Speed
1966444 - Reduced Teleport Rates
1966384 - Aetherflow
1966442 - Gear Wear Reduced
1966127 = Stealth
The Sprint buff is 1966130 in memory and you can lock it with cheat engine for perma-sprint.
Additional buff slots are at memory address hex +C.
All of these buffs appear to be client-side only, unfortunately.
1966247 - Instant Cast Speed
1966444 - Reduced Teleport Rates
1966384 - Aetherflow
1966442 - Gear Wear Reduced
1966127 = Stealth