I finally got around to making up a small batch of this seasoning last night using half a tsp of each ingredient. The only changes I made were using onion powder over onion salt and regular garlic powder in place of granulated. I just thought using 3 different salts would be a little too much. Anyway, I thought it was pretty tasty and I'm glad I left out the onion salt. It's funny because I'm not a fan of seasoning salt at all and I didn't think I had any until I reached far back into the spice cabinet and pulled out a brand new 1 pound shaker bottle that's been there for lord knows how long.
I might just keep the stuff around just to make this steak rub. BTW, I think this stuff would be killer on brisket.