Looking for thoughts on sniping unit

So I was messing around with the idea of a unit of Haemys w. hex rifles (up to 6) paired with allies for a Farseer that can guide/fortune and some pathfinders. This would be a very annoying unit IMO. Potentially very killy, scoring, and bloody hard to get rid of outside of assaulting them. Would fit in nicely with a shooting list. Maybe go lower on the Haemys and get a CC character in the unit to help with getting assaulted. Think of it inside a defense line with a gun, and an Archon or Lelith to shoot the gun.

It isn't really a good multipurpose unit though. What do you all think about running something like that assuming you balance out the rest of the army in other areas?

The idea of Farseer/Pathfinders/Hexrifles has been around for a while now but I've not seen anyone use it in a battle as yet. It's a lot of points and can potentially inflict a lot of damage.

pathfinders: DS flamers, and they are toast, or TAU ABFP 18" LB s4 ap5 assault1 ignores cover you want a sniping unite? 2 wracks 1 aco, 1 haem, 2 hexrifles, in venom w cannons. OR get GK ally vindicar assassin. i believe it doesnt even need a 6 on bs to nominate his target iirc