My tip to you, go seek an legal advice from an Asian or non-American attorney for filing your GC. There are tons in Seattle and SFO. Of course, read the reviews. They will get what you want. If you work with American-born attorney, then I am sure you will never get things done quickly. A simple mistake will restart the whole process. So make sure you do everything right at the first filing.
Question though if you're going to be company sponsored, wouldn't the company pick where you should get the legal advice from? I'm assuming they are already working with an immigration lawyer for the stuff on their end, why not just bring you in as well.