I suppose it depends where you buy it. I have a 2000CD. Paid 2000 Euros for it, but had to spend another 250 Euros for the VGA interface (monitor not included). It could be had with a free monitor in the US (when you buy the 2000CD and interface). The 2400 was only about 600 Euros more, but was out of my budget. The 2400 has the VGA interface built in, 96 kHz capability, moving faders, 24 tracks. I really would've been better off waiting and saving a bit more, but....
The 2000CD has features that the 2400 or 2480 don't have, though, like a built in drum machine (decent, not great) and USB backup capability. If I'd had the money, though, I woulda gone for the 2400.
For some reason, the 2480 is wayyy too expensive here in Europe, around 4500 Euros. So, again, it depends where you buy it.
Also depends on your needs. I don't foresee needing anything more than the 2000CD.
Best $$$ value, though, would be to find a used 1680 with FX cards.