> In this case, what would be the difference here in using a
> MOSFET or a BJT?

Depends. For the clocks I build and service which have solenoid
ratchet pulse drives (about 3A continuous), I use medium-power
Darlingtons, like the TIP121, with a catch diode across the coil

They require around 100mA base current for an Ic of 5A. A large
BJT like a TIP3055 needs many more times that for 10A Ic because
of the low gain. Plus there's the voltage drop across the transistor,
which would be at least 1V at high current. This will generate heat
and need to be dissipated

OTOH, a FET needs little gate current and when turned hard on
will not generate much heat if it has low Ron

Joe
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