It feels like syvarra’s scale is out performing vipers sting. I tried out both and even though vipers sting has got crit but even though it’s nice but if you run almost full medium due to crit change it would be out performed by scale set.
And since scale does aoe and the little 20% reduction from guards. Pve city encounter and I read that it works with guards in cyrodiil too.
Vipers sting still only does single target only.
Both damages from the sets is the same roughly
NA-Xbox one- Ebonheart Pact- Nord Tank DK
PC-NA Ebonheart Pact Nord Stam Templar