Multieffect DSP; X4 vs XD3 ???

Hi people

Does anybody know more technical details about DSPs in Ketron machines?
Technical specifications for XD9/3, X1/4 and SD-1 say:

XD9/3: multieffect DSP (although in manuals say 3 digital DSP's)
X1/4: 2 multieffect DSPs
SD-1: 3 multieffect DSPs

I know only if there are more DSPs, you have less processor utilisation for effect jobs

and everything works better. Is XD9/3 better than X1/4 regarding this matter?

Also when you use 2 additional outputs on X4, why only reverb is working on main L/R outputs? (That problem is explained in my previous topic).

Thanks