I have one of these and it worked great until salt caught some humidity and clogged up in there somewhere. I haven't been able to get it working again so far.
Put some isopropyl alcohol in the salt hopper and fire a few blanks through it. The company also sells salt with anti clumping agent in it. It's like $12, but it's like 3 years old and still not clumpy at all. Shoots great.