They're pretty good, same as the hobbico 150. They are, as you note, extremely slow, but ok for throttle on an MT. I would seriously look at something a bit faster for steering. Is there any particular reason you want digital? You can get a much better servo for that kind of money (or just a touch more) if you are willing to forgo that it is digital. The rule for digital servos that are really any good, is
$70 plus.