We have accounts at Fidelity, Schwab, and Vanguard (husband's 401k). I can't recommend Vanguard, as I've found their customer service consistently lacking/incompetent. Either Fidelity or Schwab would be fine choices.
How so? It might be more helpful if we had some examples.
Sorry, I've been trying to work on not explaining things to death unless asked, which has become a bad habit of mine. And since you've asked...
The issues started when a VBO option became available in his 401k. We made a mistake when trying to fund the VBO because there were no clear instructions on how to do it. He got several PDF booklets with written instructions on all kinds of VBO matters, but nothing that explicitly said how to fund it! There were no instructions on the website after he logged in to his 401k either. We did get it straightened out with a phone call, but it caused another month's delay in funding the VBO because of the fund trade restrictions.
After that, it got worse. My husband wanted to give me trading authority over the VBO, as he can't trade when he's at work. The written PDF instructions were wrong on this, as well as other matters. "Call this number..." We worked together on trying to get things properly set up, after he got home from work. We'd call the phone numbers as instructed, only to get people who didn't know what we were talking about. The VBO side said we'd have to call the 401k side. The 401k side said we'd need to call the VBO side. Round and round we'd go. Finally, we reached someone who appeared to understand the situation and I got trading authority.
I discovered, to my dismay, that Vanguard doesn't allow individual fixed income securities to be purchased online. No individual bonds. Not even CDs. This came as a shock, as I purchase these things online at Fidelity and Schwab all the time. Years ago, I purchased them through TDAmeritrade, so it's not like such a thing is something brand new. The only way to purchase individual fixed income securities at Vanguard is via phone. Yuck!
So, again, the phone number given by Vanguard in writing to do this, was wrong. It took multiple transfers to finally reach someone who could allow me to buy a fixed income security. Then they treated me like it was my fault for not being able to reach the right department in the first place!
This necessitated another joint phone call after my husband came home from work to find out exactly why I was getting such hassles trying to do this. Then we were given a different phone number to call which would put me directly to the department that had to put me through security first, before transferring me to the fixed income desk to finally make the purchase. Now, that shouldn't be too bad, should it?
But, they made it so. I'd get told that the whole process of verifying my identity would be simpler if I set up an online profile for myself. (IOW, I was inconveniencing them every time I needed to be put through security to make a trade, which they were getting a commission for, BTW.) I said that I didn't have an account with them. Only my husband did. They said it didn't matter. I could set up an online profile anyway. I was told this repeatedly, but of course, eventually I got someone who verified that the only way I could set up an online profile for myself was to actually have an account with them. Since I didn't, it was impossible for me to have an online profile. No kidding!
When things went without much hassle, it took about 15 minutes for me to purchase corporate bonds from one issuer! Contrast that with 15 seconds doing it online with Fidelity or Schwab. (At Fidelity, we each have POA and full trading authority on each other's Roth IRAs and can do anything needed online, with no hassles whatsoever.) I resigned myself to it. Until...
The last time I was put through security. The man sounded very insecure and uncertain. He asked me the usual questions. Then he asked me some more questions. All of which I answered flawlessly. There was nothing more I could do to prove that I am who I said I was and have authority to make the bond purchase. (Keep in mind that I was making purchases weekly for a few months to initially invest the allowed amount in the VBO.) So, after this guy took twice as long to put me through security, he transferred me to another guy who started putting me through the same security questions AGAIN!
I answered them anyway and this guy finally transferred me to the fixed income desk. After I made my bond purchase, I complained about what I'd just had to endure, needlessly.
All purchases are made online now, just ETFs. When my husband leaves his employer, Vanguard is losing our business.