|I still have my WRT54GL running but added a Linksys E3000 a year or two back because the wireless on the 54GL got flakey.|
The reason I went with the E3000 is it has dual radios (ie: 2.4 and 5.0 GHz. The radios run concurrently (this is an important feature and if you have devices that operate at only one of the two bands, you'll need to have both radios running at the same time).
So, regardless of make/model, I highly recommend you get something that has dual concurrent radios and is N.
If it were me, I'd do some price comparing. Don't forget to read reviews while deciding. Cheapest doesn't mean best.
As for DD-WRT, I was once given a 54GL that had it installed when I got it. I tried to get replace DD-WRT with my favorite 3'd party firmware and found I couldn't. I gave it away immediately and never used it in my home. I did so for two reasons:
One, I don't do firmware from people who hijack your router with their crap. If it were as good as they want you to think it is, they wouldn't do that because you would never want to remove it.
Two, Tomato is much better than DD-WRT and that is my favorite 3'd party firmware for Linux compatible SOHO routers.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.