I have to say that I love the e series. They do not have the SQ that my current equipment has, but there was always something about it that I liked. Maybe it's just because it was my first DAP.
I am actually considering buying one again to keep in my car (to connect to car stereo), because it's cheap, very durable and the SQ will not really matter when plugged into the car.
To me it's also the ultimate bang around DAP with its metal back, microSD compatibility and user replaceable battery for the very low price you can have it for right now.
Rock box makes a big difference. I also just discovered the other day that the FiiO line out plug for the ipod/iphone also plugs right in and allows line out functionality. Much better that using the head out on the unit.
I am using my old Sansa E280 since a couple of weeks with Rockbox and an 64GB SDXC card (formated to fat32) and could not be happier. Gapless, cover art and line out as mentioned above.
Just found it in a drawer some weeks ago and gave Rockbox a try. Even the old battery was still ok to use after a recharge.
Rockbox works 100% stable and is great for playing FLAC and using folder view.