The only way to know is to find out :P

Hobby motors are very poorly specified so there's not a lot of information about amp draw to go on, so it would probably depends largely on what you were using it for (weapon? drive? helicopter blades?). The only issues I know of with the Sabertooth controller are that they won't take 24v as a 24v pack will peak at well over 26v when fully charged (as Gary Cairns found out), and the current limiting is very good so if your motors are overvolted they may stop if rapidly accelerated as the initial amp draw is higher.

Hope all that helps.