I bought 2 different models of Asus routers that were b/g. They worked great with DD-WRT for almost exactly 2 years, then they died a week apart from each other. Bricks. I replaced them with a WRT54GL. My backup for it is a WRT350N that someone gave me. That's right, the ol' 54GL is more dependable than the fancier 350N.
I'd consider Asus again, but only if I could convince myself to buy 2 so I could have a standby for when the first died.
Just consider this... do you really need the N spectrum? I don't personally do a lot of file transfers between computers on my network where speed is a consideration serious. If I was to saturate the whole allowance of G trying to hit the Internet, that's still more than what my outgoing cable internet service provides with Time Warner.
Moreover, to get full N, you have to broadcast 2.4 and 5 spectrums, and only one of the two goes far enough to get out of a room and through walls, so you effectively have G speeds in most N implementations anyway. Read about it... lots of people turn N off and go back to G, even when they have access to the fancier feature.