I’ve found I can I push money really quickly from Fidelity Brokerage into Schwab Bank Checking, if I put in the request at 8 am the funds are there by noon. Since Fidelity’s cash sweep is money market (I use Fidelity Treasury Money Market Fund FZFXX), it’s earning almost 5% until the moment it leaves. You can’t do this at Schwab, I’d have to manually sell SNSXX over there, then wait overnight.
Since I’m using Schwab Bank as the payment account, I avoid the flakiness of Fidelity Cash Management which is a fintech joint venture between Fidelity and UMB Bank. There is some incidence observed on Reddit of Fidelity Bill Pay not being totally reliable, after which UMB and Fidelity start the finger-pointing at each other.
Also there is overbearing and paranoid backoffice security at Fidelity, which really hasn’t figured out how to function well with payment accounts. If you get your account locked up, you cannot appeal to CFPB. Fidelity Cash isn’t legally a bank, so you have to appeal to FINRA; good luck with that.
I think the best of both worlds is to use them together. They both use app-based multi-factor authentication, which is better than most banks which still rely on text message MFA, which is not as safe. Schwab customer service is better than any bank I’ve ever dealt with, another reason to use them as the banking leg.
Plus if you use F and S together… you avoid keeping your money in one place. That’s the most important point.