Would a weaker power source make the SSV not perform as well? For example my house is very old and the outlets don’t work very well sometimes, and I feel as though my surfer doesn’t work as well as the ones in the shop or at parties cause of it.

Sometimes at parties the wind can make the Surfer run cooler.

You should have 110-120 volts in your home, both will make it work as it should.  Many times if the unit is not getting hot enough it is because the heater is too low.

Learn to adjust your heater here.