Best external HDD under $250 to use with the rMBP?

[PhaserFuzz]

Hey guys, I'm looking into getting an external HDD to use with my rMBP. I would like to stay under $250 if possible. I don't need more than a terrabyte in space either. Also, I'd like one that I could just leave plugged in and not worry about, if that's even possible. Any help would be appreciated. Thanks!

 

[simsaladimbamba]

Does USB 3.0 suffice, because many USB 3.0 HDDs can be had for less than 100 USD, especially ones with less than 1 TB.
Maybe invest into two HDDs to have a backup of your backup, if you have important files.

I have one 500 GB HDD for my photographs (digital and analog) libraries and editing documents, one 500 GB HDD with my personal video footage in an editing friendly format.
Both 500 GB HDDs get backed up to one 1 TB HDD via CarbonCopyCloner.
And that 1 TB HDD gets backed up to another 1 TB HDD via CarbonCopyCloner.
Therefore I have three copies of my important data.

 

[heisenberg123]

ive always been a fan of western digital externals you can get a 1TB USB 3.0 for about $99

 

[PhaserFuzz]

Is it safe to just leave it plugged in at all times? Or will that damage the drive?