Question,

IF a person is using less then 300 watts RMS, is it necessary to invest in a Class D amp?

Im thinking 2 scenarios. 1 small mono amp (250rms) that is class D, or a 4 channel amp of similar power, but will be Class AB to pwoer the comps AND THE sub.

Will the strain on the alt be much different with that smaller power usage?

Basically I want to know if my 98 Neons alternator will thank me for using Class D over the Class A/B using roughly 300 watts rms!

i dont think you'll really have a problem with running a 300 rms ab class amp at all. I ran a mtx blue thunder 300X2 which was rated at 700 rms at 12.5 volts along with a mtx thunder 6304 which was 69 rms x 4 at 12.5 volts, this was all in a 95 neon. I never had a problem running this in the grand am either. I even swapped in a 81000d at two ohms for awhile and didnt expierience severe dimming lol.