<prompt> Human: Im just starting out in investing and saving for retirement. Ive been told that Vanguard would be best for noobs. But does that mean I have to stick to Vanguard? Can I switch over? Can I open an account with Vanguard and Fidelity? or will this cause issues in the long run?Which one will yield more money in the long run?And if someone could just summarize the differences and benefits of each one, that would be great.Any recommendations from your personal experiences?Thank you in advance!  <response>: They are all about the same provided you invest in broadly diversified, low expense ratio index funds. 