what is the better gauge for any of these applications?

boost/vac gauge. - mechanical vs electrical ?
fuel pressure. - mechanical vs electrical ?
water temp. - mechanical vs electrical ?
oil temp. - mechanical vs electrical ?
oil press. - mechanical vs electrical ?

keep up the good work.

add other gauges if you want...

 

This would be my opinion:

boost-mech
fuel pres-elec
water temp-elec
oil temp-elec (sensor is in pan)
oil press-mech

But whatever works really