In my opinion, the Ultra Series (e6400, E4XT if you need 32 midi channels + 128 voices polyphony) is a hit.
The EOS v4.7 offers a lot if you like sound design.
One of the advantages of the Ultras is their ability to connect to IDE hard drives (I have a 160 Gb on board).
Some users will probably point you to older models (seems like the filter grain sounds better to their ears) ...
In my opinion the filter on the Ultras sounds wonderfull (to me). These machines will give you a texture you'll never get with any soft-sampler (I've been a hardcore user of Kontakt before, which I like btw - programmability, etc.)
I both have a e6400 + E4XT (Ultra) and I use them ... everyday
Olivier