in my mac, i removed the CD drive and put a harddrive in there... it frees up a USB port for me, since macs only have 2...
I wouldn't say Internal Drives are "faster". It really depends on the read and write speed. My 3TB external drive is way faster than my Internal 1TB. I copied my buddys HD and he had 700GB, It finished in like 8-10 minutes. So the short answer is look for good read and write speed and invest
Well, this is difficult. External is portable, you can easily take it with you wherever you go. Most of the times, portable is also a disadvantage for e.g. thiefs. Internal's disadvantage is that you can't take it easily quickly out if you need it somewhere else without your desktop/notebook. The advantage of the internal HD is that you could choose self which HD you would like to use, think on speed, capacity, quality, warranty. As the most internal harddisk like WD RED PRO has a warranty period of 5 year or longer, the most external HD's only have 2 years. Even if there is a WD RED hd in it. My opinion, choose the internal and make an backup on an external harddisk.
the super small external with the 3.0 ubs is what i like best, super fast transfer and i have it for my different computers or laptops
Western Digital or Seagate Hard drive 3.0 1tb or 2tb works awesome. surely shouldn't have a problem. might be a couple seconds slower than internal but nothing major.. you will definitely see the speed tho internal if more faster but may also slow down yr laptop. so i use a 3.0 segate 2tb just as fast and im protected at the same time
External with a fast connection (usb 3.0 or firewire). Less of a burden on you laptop. For DJing puposes.