Galaxy S5 will defiantly have a locked Bootloader. Its Samsung duh..
HTC One M8 may have an unlocked but from experience with owning an HTC Device, it'll probably be locked. And on top of that it has "s-on" security protection.
I can tell HTC One M8 will be a solid phone for techy and music lovers. Where as S5 will be a choice for people that just want to get up to date specs. Idk its a question we have to wait for till its answered when released. One M8 has probably been released.
The sash wringing... the trash thinging... mash flinging... the flash springing, bringing the the crash thinging the...