I considered the EG4 18k but there was people talking about issues with them and bad customer service from them. I do not know a lot about the Sol-ark 15k but know it is similar to the EG4. After reading about the Schneider it sounds like its made like a tank and great customer service. I have not committed to anything yet, that is the one I am considering the most as of now though. It will be a few months before I really start setting up the solar stuff as I just bought the new house, have my new shop to build out (have epoxy floors being done next week in the pole barn, then start on the shop), moving all our crap from my current home to the new and then doing some work on the old house to get it ready to sell.