Galil, Kflop/Kanalog combo, CSMIO/IP-A are the three that I know of, other than DSPMC, that can supply +-10V to analogue amps.
The CSMIO uses full encoder feedback for lathe threading which means it can follow the spindle precisely even if the spindle is grossly underpowered and slows to almost a standstill, in fact it will even continue after a full stop of the spindle but in real terms that could never happen as a stalled spindle could never restart. It does however have issues, it will delay the pull-out at the end of the thread thus cutting an annular groove (if there is not already one there) For some threads this may be acceptable but for others not.
It is a Mach issue in the way the info is fed out to the plugin and it seems nothing can be done at this time, although I recently discovered a different version of Mach did things much better and the pull-out was almost instant. I have not found out what the changes have been as yet.
The Galil also had this exact same issue when trying to use full encoder feedback (ie axis to spindle sync ) and they reverted to the standard single Index feedback and that works well, by all reports, as long as your spindle is not grossly underpowered.
I do not know how the Kflop/Kanalog combo does things but I do know for rigid tapping with it you have to do extras in your code but single point threading I think is just standard, so again would presume as long as your spindle is adequate there will be no issues.
Now MPG, I do not know if multiple MPG's can be used on any of the above. The CSMIO uses an external module for MPG and it is the nicest motion I have seen on a controller but it can only use one MPG. It may be possible to connect MPGs via normal inputs but I have never tried and not likely to as I have no need for that.
Rufi had mentioned to you that Mach Rev4 will be needed for this with the DSPMC and I do know that things will be done very differently with it as it has been designed around the hardware interface instead of the parallel port interface, this will mean that anything the parallel port can do an external controller should be capable of and of course the things that the external controllers do , at the moment, better than the parallel port willl also continue.
Hood