Best HDD mirror/backup utility

I have two WD 4TB external USB drives after I outgrew my last 2TB. I got two to make a back up of one after a friends drive crashed and fear of it happening to me. Drive 1 is an HGST Touro 4TB (WD internal drive) - love the case but is extremely slow I guess with seeking? Takes a while load up quite often and is very irritating. Drive 2 is a WD 4TB MyBook that I haven't used yet besides to test with different programs for DOA.

Basically what I want to do is mirror Drive 1 onto Drive 2, and have it overwrite any changes I make, weekly-ish or how ever often I set the schedule, to Drive 2 (similar to when you make an on-the-go playlist on your ipod it copies it to itunes). I have tried a few programs just using test folders on my desktop and haven't liked the format or the extra folders they created. I want an exact mirror, and the ability to flip if I find out that Drive 2 is quicker for daily use (I use Drive 1 daily as a storage unit for all important data, movies, files, docs; not just as a backup device an stays powered up 24/7 due to no power button and only gets unplugged if I go on vacation)

What do you guys/girls all use and what are the pros/cons? Thanks in advance!

Could potentially use robocopy for this.

http://caughtinpixels.com/how-to-cre...sing-robocopy/

This link has a decent walkthrough to give you the general idea.

This isn't really a "backup" solution though, since it wont save you from accidental deletion nor corrupted files. It can give you an exact mirror of the files at the time of the "backup" and you can flip it easily, but won't give you the benefits of a backup solution like Acronis True Image or Macrium Reflect. Having incremental and differential backup options so you can recover from specific dates as well as being able to do bare metal recovery makes it worth it for me at least.

I've been using Macrium Reflect, I like it a lot so far. Thank you for the insight