Forget all that
By all means, get a Kurzweil. Not only do they have the best support in the world (they continue to maintain and support their K-line instruments for at least 10 years now), they are known for the best Piano samples on a keyboard, and their V.A.S.T architecture technology means you will honestly, probably never outgrow the instrument.
I have had
my K2500XS for 6 years and I still feel like I have barely scratched the surface of the instrument. Kurzweil has since come out with the K2600, and the K2661 (a 61 key version loaded to the gills with a synth key-action keyboard).
The specs are too numerous to list, but not only are their sounds extremely lifelike (orchestral, piano, etc.), but with the numerous algorithms and KDFX baord (probably the best Effects board in the world inside an instrument with some of the finest engineering anywhere. When reviewed, editors noted that it was probably as good if not better than stand along Hardware effects units costing over $2,500.)
You should not buy anything until you have spent time studying and talking to a Kurzweil rep. You won't go back elsewhere.
The only reason you don't hear too much anymore in the news about Kurzweil, is that their flagship keyboard (now the K2600) is so hard to improve upon that it has stood the test of time and they have not come out with a K3000, yet.
When they do, rest assured it will be backwards compatible with the K2000, the K2500, and the K2600.
The K2600, (and
the K2661) come standard with Hardware sampling, KDFX (this is too awesome to even describe, but it will take you a long time to get your brain wrapped around it.. it's just that powerful), arpegiators, KB3 (which is arguably the best realistic Hammand B3 organ sound, Period! I cannot tell the difference between my KB3 sounds on my Kurzweil and a real B3 organ when side by side. You can use the 8 sliders on the Kurzweil and the Mod Wheel, as though they were the 9 drawbars of a real B3 changing the sound at will), LIVE mode... which means you can run any sound source directly into your Kurzweil and use the V.A.S.T. processing power of the Kurzweil to do wonders on your LIVE input sounds, oh.. yes.. it also has VOCODER, Sequencer (of course) and heck.. all the best studios in the world have Kurzweils.
Let me explain one thing, that not only you but many people ought to hear:
The only synthesizer I know of that has individual effects maintained as part of the original program (your great Rhodes piano, for example, and then add some high quality reverb to the sound) is
the Novation Supernova II.
What does this mean? Well, as almost all synth users know, going way back in time to the even the early 1980's.... when you created a synth patch (program) with cool effects... that program might very likely lose its effects that you had chosen for it, BECAUSE.... this is important, so don't lose sight of this.... BECAUSE when you ported your Programs (Patches) into a Multi mode setup (or Combi, different manufacturers use different words to mean the same thing)... you almost always had to choose between one Program's (or Patch) effects.
Therefore, your Bass guitar patch with Compression, and your neat synth pad with Delay... and your Kick drum with boosted bass... etc... could not all maintain their effects simultaneously. You were forced to choose one Effect algorithm for the whole Setup (or Combi). This always sucked and has continued to be a bitch for us players and keyboard programmers to deal with.
With KDFX in the Kurzweil, you are able to use up to 5 different Effects at the same time... so in a Song, or a Setup (Combi).. you can program each different sound with a different effect. This, as you will come to find, is extremely important.
The Novation Supernova II, does this with up to 8 programs playing at once. I own one of these, too. Very impressive.
I suspect that this type of thing will start to catch on with other manufacturers eventually, but thus far, only Kurzweil and Novation have keyboards that offer this.
And if you get a Kurzweil with the weighted keyboard, I believe they are the best weighted keyboards anywhere. I tried them all, including stand alone MIDI Keyboard controllers, and they were not as good as what comes standard on the Kurzweil (with weighted keys).
Almost no limitations and seemingly endless ways to route ideas in, though, and around this machine. And if you get into a Digtal Audio Workstation (DAW), the Kurzweils have 8 separate stereo OUTs (Analog, Digital Coax, ADAT suport, and Optical) so you can wire your sounds to whatever channel you wish when recording. Mind boggling power.