Hi Mongoo,
The Akai DOESN'T record 24 discreet tracks at 24-bit; it does the same thing as the Yamaha and Korg (as far as I have been told - I HAVEN'T looked for myself, I just know all of these"all-in-one" workstations allocate bit rates according to track count and particular algorithms to make space and to make the units small) It records 24 tracks at 16-bit, 16 at 24 (44.1) and I guess 8 at 24-bit 96.k (which is hardly discernable in terms of the sample rate increase; 24-bit at 44.1k is perfect and the current industry standard)
What I HAVE seen about the Akai that's cool is that it uses industry standard 100mm long-throw faders, which is important because the db increase/decrease is more subtle because of the long taper, and it has knobs to tweak eq and sends rather than a mouse or data/jog shuttle.
But it still is in the dust when compared to workstations like the SX-1LE and some computer rigs, such as Nuendo and Pro Tools etc (digi 002 is pretty powerful)
I guess it comes down to preference and as I stated somewhere else here, I have done several commercial projects on
a Yamaha AW2816, and they sound great. The thing about some of the higher end workstations (and the SX-1LE has complete waveform editing, 5.1 surround capabilty-which is the comming audio wave of the future - a sequencer and complete VGA support, and it costs about THE SAME as the Akai!) is that they are commensurate with what their computer based counterparts do,like waveform editing, 999 levels of undo, 999 virtual tracks - all of that sort of thing. It's also a matter of your requirements.
At least you are doing serious research, so you'll get what you need. Just understand that most of these workstations make some concessions somewhere, and it's really a matter of whether you accept those concessiosn or not - and THAT always has to do with budget, and we've all been there! But the concession field is narrow these days, and you can make great recordings with just about any of them.
So good luck dude!