IDK too 
i guess some people don't like swapping that much. but when i had Tirfing Valk i used Garm armor for extra defense.
i use Bathory & +8 Tirfing Guard now.
Ya, you really don't need epic gears to do niff. It always has enough people in it that you can't make huge ass mobs that you can't handle. So if you use decent gears you can do just as well as anybody else there. Tirf valk is just a waste of money cause you can niff effectively with a plain ol' tirfing guard. use garm or bathory depending on your preference (bathory is cheaper and works well there). DL valks, devi muff/mant, a hell poodle ring and soul ring and your pretty much set. Throw in a vanberk if you liek the crits or just a simple myst case mid if you just don't care. DBSS mace works beautifully there and kills the mobs fast enough (though mjol is better). You can do niff just as well without mjol.
Honestly, it's just too simple to niff and the gearset is pretty cheap. I don't see why everyone doesn't try to niff. The place usually only ever has like 5-6 ws's there when I go
P.S: There's my simple niff guide for teh nubs...
