First, spend the extra and get the DP-32 (instead of the DP-24). Now, the DP-24 is a good sounding board. It is clean.
Tascam did a brilliant job in many ways with the DP-24. It is important to know that there is no hard drive or moving parts. The pre-amps are stable and consistent. The feel is very similar to working with a tape mechanism. But, it is much faster of course. I really believe this board is capable of delivering the magic you need to produce worthwhile pieces. Please make sure you are running the latest firmware.
Now, for the downsides. When adjusting the EQ, every click of the stateless knobs corresponds to a linear value. This means that the knob can take several rotations to go from min to max. From an artistic standpoint, it is like having to depress the piano harder (three times) to achieve maximum level on the note. This really gets in my way, but only from an artistic sense. It would be great if the firmware version had a global multiplier that would allow one click to equal +3 or -3 for example. This way you could go from min to max in less than one full rotation of the knob.
Next, since the entire thing is sold state, it is prone to crashes. This is rare and is much improved with the latest firmware, but the DP-24 will crash once in a while. You generally won't lose much, but it is still shocking to watch your production get hung up on a brain dead DP-24. I do a lot of editing and that seems to trigger the crash. Do not let this deter you from purchase as it is very rare.
Another issue, that really bugs me, is the very limited resolution of cut and paste operations. The solution is to use "bars" instead of minutes/seconds. But, even here, you can drill down and visually see a sound that you want to mute or cut. If your I/O selection interval is too short, the bloody thing will reject it. You can get around this limitation by inversion, but it takes multiple operations to conduct a simple cut .
I don't understand why this limitation exists, but you can't drill down to fractions of a send too well. You can see it, but the system won't let your selection take place unless it is long enough.
Another big disappointment for me is the lack of vary-speed simulation. There is no way to slow down or speed up the virtual tape. Again, this is an artistic restriction that really gets in the way.
Splicing (cut and paste operations) usually works well. But, every now and then you will get a "pop" that did not appear anywhere in the recording. Yes, you can see the "pop" visually, but it can be a pain to mute it if the pop lands near anything but silence. If you try to grab on to an i/o interval that is too short to clean the pop, you will get an error. Again, you can use inversion as a work around, but this can be time consuming.
The effects can be tricky to master. There are limitations that can get in your way. But, the work around is that it takes more time.
For these reasons, you need more tracks available to overcome of the DP-24's limitations. The virtual tracking is a gem. But, sometimes it is more efficient to use the slot.
You see, the DP-24 is a work of art---especially for anyone who grew up using a board. It is this beauty that takes you down the path of wanting more and more. And this is where you hit the limits.
The lack of a hard drive is a blessing in that it is really cool to be working on a silent, monolithic, all encompassing piece of hardware. The lack of hard drive is a curse, since I suspect a lot of the limitations I describe are due to processing restrictions related to the slowness of writes in the SDHC memory chip.
Finally, one concern, is that it appears that the DP-24 is limited to a 32 Gigabyte memory card. So, this may get in your way four years from now when 32 Gigabytes goes the way of the floppy disk.
The DP-24 is not the NEO.
I think the future in this technology will be in the realm of control surfaces combined with pro tools, etc.
But, the DP-24 is exponentially cheaper than a high end pro tools with high end control surfaces.
The DP-24 is FUN to use and you can express yourself artistically. I urge you to consider it and don't be discouraged by comments.