Well... I've been in the garden since last July and I told myself I'm only coming out when the Schwab Amex became available. I know there are better cards out there, but Schwab has been good to me from a customer service perspective, and I've been pleased with Amex the past year in collecting MR points with my PRG. So, I applied and was approved for....
$20,000.00 
This is my highest SL for any card!!! The only card with a higher limit is my SPG which almost took me a full year to get to 25k. Anyways. A couple things to mention:
I have a checking, IRA, and Investor account with Schwab. The checking (rarely used) is backup to my primary and I opened my Rollover IRA last year. However, I don't think that made a difference in their decision, as the process seemed like I was applying for an Amex and not Schwab (Yes, I was at schwab.com and I had to login into my Schwab account). At first, it didn't show my CL after it told me I was approved, so I went through the process of getting my card number. There, it showed my limit! Thereafter, I received an email from Amex. Not Schwab. So, I was able to add my card to my Amex account and confirm that my limit was indeed $20k.
Other details... They pulled Experian (Description says Amex not Schwab Bank), I had a total of 6 inquiries. Again, the last one being from July 2015, and the oldest from Dec. 2014. Well, that's it! I'll remove my gold spade now... 