I love Vicious ophidian, for solo pve the speed buff for killing stuff is fun, I remember my first experience putting it on, it was way back where it also was amazing for group dungeons, still is, however better options out there now.
I was with a group in wayrest sewers dungeon and after we killed the first rats, the speed which I weren't used to, just made me run right into the crocodiles and get eaten before the tank could react
totally my fault for that death
ever since thats been one of my favorite stamina sets for solo stuff, especially in veteran maelstrom arena as well, you kill stuff run faster then other mobs, so they cant hit you, plus you get stamina return for kills too
PvP: Pirates + something else (crafted sets like Hundings, NMA, ancient dragon, shacklebreak all are nice for PvP) impen trait preferred
PvE: VO + Leviathan (divine trait preferred)
PVE: VO + Leviathan is great until you can get endgame sets like Relequen, if that's what you're looking for. Leviathan is a strong crit set. I would run it over Hundlings if I was going to run it with VO.
VO is a strong set geared for solo-centered/small group content like VMA, VDSA or VBRP. VO + Twice Fanged is a great combo for that. Or like others have said, VO + Hundlings is good too.
Check out Briarheart as well for PVE.
Finally, BP is not really a set you want to run for PVE. Yes, you get TONS of stamina, but you lose tons of damage buffs. Sustain is easier in PVE than PVP, especially if you have a full set of VO. I would definitely NOT run BP with VO. Its overkill in the sustain.