depends on how many inputs you need.
i got the Q10 so I can have more options for recording say, a drumset..or more than one instrument at a time.
I really like the unit, the sound and the preamps are fantastic for the price.
the nice thing about the 2496 is that all 4 of the channels have phantom power, on the Q10 you only get 4 as well...the last 4 are not, which is fine really...
But they are built on the same core...and, have a lot of the same features. I am not sure if the 2496 has the word clock output? Which I am finding can be a really valuable thing to have.
good luck.