Just following up here... it's been a couple of months, and so far everything has worked flawlessly with the Schwab checking account.
I've read in other places that ACH transfers can be slow, but my experience has been the exact opposite... it's not unusual for my ACH 'push' transfers from USAA to show up at Schwab the same day (usually around 7:30pm ET). Definitely no complaints. 
I've not tried to do 'pull' transactions (or 'push' for that matter) directly from the Schwab dashboard - perhaps that's what others are having issues with being slower than desired. My 'pull' transactions initiated from USAA have all worked just as expected (USAA giving immediate credit is an added bonus). Having USAA makes it really easy to get money to/from the Schwab account, even without using the Schwab ATM card or checkbook.
Anyway, for anyone who might be on the fence hopefully this additional info will be helpful.
@UncleB wrote:With the rate on redeeming MRs changing in a few weeks I decided to go ahead and make my redemption into my brokerage account (which was the entire point of getting the Schwab Checking and Platinum card to begin with).
The redemption was straight-forward, and the final message on the Amex site stated that it would take four to six business days for the funds to show up in my Schwab brokerage account. Further, it stated that if I had any questions about the redemption to contact Schwab. The MRs were deducted immediately, and for giggles I checked Schwab and there was no change. However, just a few hours later I checked Schwab again and the funds were there, which was a pleasant surprise.
I was able to do a transfer the entire balance to my Schwab checking account, which seemed to be immediate (no holds). I'm going to wait a day or so (for good measure) before writing myself a check but I have to say the process was absolutely seamless.
Aw you are so lucky! The "check is in the mail" so to speak! 
@UncleB wrote:Just following up here... it's been a couple of months, and so far everything has worked flawlessly with the Schwab checking account.
I've read in other places that ACH transfers can be slow, but my experience has been the exact opposite... it's not unusual for my ACH 'push' transfers from USAA to show up at Schwab the same day (usually around 7:30pm ET). Definitely no complaints.
I've not tried to do 'pull' transactions (or 'push' for that matter) directly from the Schwab dashboard - perhaps that's what others are having issues with being slower than desired. My 'pull' transactions initiated from USAA have all worked just as expected (USAA giving immediate credit is an added bonus). Having USAA makes it really easy to get money to/from the Schwab account, even without using the Schwab ATM card or checkbook.
Anyway, for anyone who might be on the fence hopefully this additional info will be helpful.
I have also been learning the ropes at Schwab recently. Transfers into my brokerage account from US Bank were taking about four business days to post. That was annoyingly slow, so I wanted a faster way. I'm not eligible for USAA membership.
I opened a checking account with Schwab, thinking their debit card would enable to me to deposit cash at an ATM. Only after I had opened that did I learn it's not possible to deposit cash with this card. Oops!
Eventually I found a way to move funds in quickly: Write a check to myself (drawn on a non-Schwab account, of course) and use their mobile app to deposit it. The funds show up in just a few minutes. I find it counterintuitive that this is the fastest way, but I'm glad I found something workable.
Schwab Bank now has Zelle. Cool!
(Edit: I now see that @UncleB beat me to it by 8+ hours in a new thread. So close! 🤪)