Still more of a showcase than a day to day FE though.
Agreed with FT.
I used to use 3darcade as my main frontend, but what it boiled down to is that it tended to intimidate and frustrate rather than help people (noobs to my 'arcade') find games. It was extremely customizable, including having a nice 3d engine involved for a FPS style walkabout for your own virtual arcade. Also of note, was a lot of scripting which allowed for flash-type menus and options. Since I'm not a big fan of Flash (nor do I understand it), the 3d option was the way I took, although there are your basic 'list style' options available.
If you have the PC to run it (requires some beefier settings depending on how you set up your 'arcade') and have the HD space for all of the various excellent cabinet/pinball models out there, AND have as many screen snaps, titles, sidearts, marquees, etc as you could possibly find... you can make some pretty sweet setups in an inordinately small amount of time.
I found that I was having more fun with my cabinet spending time playing the games than spending time playing with the front end, so I switched.

The thing that sold me on it in the first place was a flash-based menu interface that was pretty well much Galaxian (Galaga?) where you 'shot' at badguys which represented various lists and options. The customization was great, but I ended up getting more involved with 'tweaking' my setup and making it all sweet... which then made it horribly annoying for another user to come into my garage and figure out how to play Pac-Man. (Hint: You shouldn't need a bezel's worth of instructions to explain how to use your super-tweaked FE menu interface!)
3dArcade has a *ton* of fun stuff out there and it feels like it's infinitely customizeable , but if you're looking for something small (filesize), light (on your processor) or simple, you might want to try another FE. Either way... it can't hurt you to try it out!
http://3darcade.mameworld.net/