Hey realdeal.
As far as good tapes, yeah, they're actually fairly good, from what I've seen. But most tapes will be a decent quality.
I encourage people to stick to the tape brand they've been using. To make the tapes run through the camera smoothly, manufacturers coat them with a very light layer of lubricant. This lubricant transfers onto the head, control arms, guides, and everything else in your DV VCR. That's all fine and such, because it won't affect your unit, so long as you stick to the same lubricant.
However, every tape manufacturer uses their own type of lubricant on their tapes. What that means is if you have a Sony DV tape in your camera, and you then put in a Canon tape, for example, two different lubricants are getting mixed together on the heads. Initially, this might not sound like such a big deal, but here's the rub: some of these lubricants are reactive to one another. What I mean is that when you combine them, they can actually turn into a pasty substance with adhesive qualities. NOT the sort of thing you want in a very touch (and potentially expensive) piece of machinery. Switching tape brands can very literally leave you in a very sticky situation.
I bought all of my cameras that I currently use new, except for one. The videographer who sold it to me only used Maxell DV tapes that he got from Sam's club. Well, to avoid messing up the cameras, those are the tapes I now use. It's something like $24 for an 8-pack, tax included, and I've only one time had any sort of problem with them, which may even have been my doing. For three bucks a tape, I'm happy.
If you did want to switch brands, I would highly suggest that you buy a head cleaning tape, and run it through a couple times before you make the switch (DO NOT over-use it, or you can damage your head, a very expensive mistake!)
Hope that helps!