Rock steady. Put a crank trigger on, you will never go back.
I always used a wheel with the magnets in it. No reason not to. Have spare engines, you can just swap the stuff as needed.
Depends on what is going on in terms of pulley spacing or what else is being driven off the front. There are a lot of reasons to get rid of the magnet wheel such as dry sump engines or engines that don't have much space for pullies.
