Chris,
I work for Salem Controls and can give you some info--of course, my opinion is slightly biased
1.8 amps is no problem, this board can be run up to the full 2.5A. Also, torque vs. speed info is given for most motors at 24V, and depending on the rated voltage of your motors the gains at voltages higher than the 24V range may be insignificant.
If you have any questions please send me an email or give me a call--contact info is on our web site at
http://www.salemcontrols.com/contact/contact.html
Thanks!
Daniel