Thanks for reaching out. It really depends on what you're looking for, and I don't want to hijack this thread with a long discussion, so feel free to reach out at https://scalyr.com/contact. If you're focused on the power of the query language, then Splunk is the undisputed leader, but we are relatively strong as well; see https://app.scalyr.com/help/power-queries. This iteration of our query language was launched last year and was a lot of fun to build -- the team allowed me to write a fair amount of the code. :-)

You can find a more general overview at https://scalyr.com/product.