I believe any 1.9 hacked client will work for 1.9.4 clients. Most server's support all 1.9.x clients. Pretty sure it doesn't matter.
I'm having a hard time finding clients that are updated to 1.9.4 - I am specifically looking for Huzuni 1.9.4. And mainly for it's autofarm function.
and also - is there currently a client that allows you to adjust the x-ray block settings?
I've been using Wurst, LiquidBounce, Matix, and Impact.
I believe any 1.9 hacked client will work for 1.9.4 clients. Most server's support all 1.9.x clients. Pretty sure it doesn't matter.