Red is for NAS i think, stay with Blue or even better, Black for internal HDD. If you want 4GB to store your movies/serials/korean dramas/music/anime/prawn/etc, I think Hitachi Deskstar is better priced.
You can see my fairly big review on the page; think it was a 2 star. For some reason the review was rated not helpful by quite a lot of people; I guess they don't like that I'm using a 24/7 rated drive (read: better reliability than consumer drive) in a non-NAS environment, really boggles my mind.
As they're being used in a personal environment (not a room with a NAS box), the noise is a big problem, especially if your PC is silent. It's possible 1 drive is tolerable, but having 2 setup in a RAID is a nightmare for noise.
I ended up replacing them with Seagate's NAS drives, which are a bit quieter and faster to boot. They also have a lot quieter access noise compared to WD's, and a very different tone at that.
If you're writing up to 1080p30 footage, the drive should do just fine, but going higher (1080p60) will require multiple drives or an SSD, as that's like 200-250MB/s writes, more than the drive can keep up.
If you're really serious about high quality video work (above 1080p30), I'd grab 2 drives and use Dxtory to split record to both; or setup a RAID0, but that's less reliable. Hell, it might even be needed for 1080p30 if it gets near the end of the drive.
Thanks for the replies everyone, Noise isn't that big of an issue to me, but if it's really that much louder than the 1TB black I guess I'll pass, and the videos will be 720-1080p & 30fps since that's the maximun on youtube, might do higher if I upload somewhere else that supports it, and if i was to buy two Reds then I rather go with a single 4TB black instead since it be cheaper anyway, I don't want to spend more than $200 but if I have to I'll add $50 at most.