Help Info on using multiple email accounts

[cdl]

I will probably use two email accounts, one imap and the other either imap or exchange. I'd like an imap idle client, probably k-9.

Could anyone tell me what the options to manage such accounts are, with the integrated email client, k-9 or else?

Specifically, I'd be interested in a consolidated view that combines the emails received from both accounts, so that I don't have to constantly switch from one to another.

Thanks!