I never use webmail/IMAP. Simply put, I don't trust it. There are too many anecdotes of searches without a warrant, snooping by webmail provider employees, webmail providers changing their terms/discontinuing their service offering.

I want my e-mails in my e-mail client and ONLY in my e-mail client. My client uses TLS encryption to connect to the server for both sending and receiving, and that's pretty much that.