I don't bag, but I do brush all the time. However, the brush I use is not a regular mane comb; it's a metal mane comb that has rotating teeth. It's called a Grooma rake. I can brush out all of Brandy's mane, tail, and forelock (which are all very long!), in about ten minutes. And there is no hair loss if you start from the bottom and work your way to the top. It is actually pretty hard to tear out hair even if you wanted too. It's awesome for getting burrs out, too. I have had it for two years now and it has held up to fairly heavy use. You can use people brushes, too. They are generally better than regular mane combs, but not as good as the Grooma rake I have.
I condition my horse's tail and mane every time I go see her, and especially before I brush it out. I have found that Fructis sleek-and-shine leave in conditioner works wonders. You can find it with the regular people conditioners. I have also been banging her tail to about fetlock level lately and it grows sooo much faster (split ends are gone), and looks fuller and healthier.
My riding instructor bags one of her horse's tails and it does help the length. But, I have stayed away from that because I noticed that it made the top of his tail scraggly and short. My horse's tail is a lot healthier than his with what I've done, so I'm never bagging it if I don't have to!
Here's the link to that awesome comb. Lol It has 4 1/2 stars! Grooma Rake - Grooming Tools from SmartPak Equine
P.S. A friend's groomer asked where my friend got her dog comb. We gave it to her... it was a Grooma rake, and the dog groomer loves it. The dog is an Afghan, so you can imagine what a pain it could be to brush out a dog like that!