Hi Lula
It's really up to you, I have been using cheap $5 Panasonic's since 1999 and the footage is still there just like the day I shot it. Yes you may get a dropout now and again but it's not very often. I even use the same tapes in my SONY HDV camera's now.
I have also used some Premium $$$ DVCAM and HDV tapes and have gotten dropouts on them too so go figure.
You don't need to record black on the tape unless timecode is very important to you. What can happen is there might be a cut in time code if you don't que the tape back up after reviewing it or after you took the tape out of the camera and then put it back in and don't que it up to where you stopped filming on it so when you press record it starts from zero again.
Most NLE can keep importing even it it comes too a break in the timecode while you are fire wiring in.
I do recommend that what ever tape brand you go with stay with them due to different lubes on the tapes. Early SONY tapes where really bad and if you put in another type brand after using them it would cause all kinds of problems. SONY uses a different lube now days so it's not much of a problem. If you do put a old SONY premium tape in your camera, use a head cleaner before you put another brand in. I did this the other day and the camera would not play the image of other tapes until I put in a head cleaner. Another good thing is record nothing for the first 30 seconds at the start of each new tape.