Has anyone played with eureka? Trying to see what's worthwhile, and what's not. I think this got lost in the posts.
I played around with the dusterline. They're partly nice cause you can directly turn cobblestone into sand when you need it. (for metal it's pretty useless since of all the other stuff like fortune-hammer and tinker's construct)
The RF-duster is okay, but you need to put in everything manually, one by one. The kinetic one... well it combines being able to put in things with hoppers and pipes... but the lasers takes alot, really alot of energy to actually work on it. With 1 laser you're alot faster just hammering the things down and more than one laser... you need more energy-production (a stirling-generator with the octu-upgrade you get through a quest cannot deal with 2 lasers).
So all in all the kinetic-duster is nice if you just want to turn alot of cobble into sand without caring too much about it. But you need a steady energy for the laser for it to work. (so pretty much after you have a charcoal-farm, not earlier)
Oh and one thing I got confused with: The dusters/machines that work with inventories -> you need this "configuration tool" to tell it where to output/input things. Input works with hopper fine without configuration, but output... without configuring this it just spits the items everywhere