i took off my factory speakers and saw that they said the speakers were 25 watts. is that their max rms? or normal rms? and how would these compare to 40 watt rms-normal (max is 240 watts)?

 

If they're 4ohm drivers It's probably 25w RMS. That's just a guess based on how much power an OEM stereo can put out with out an amplifier.

As far as which will be better, it depends on a number of factors including efficiency and how much power you're giving them and the overall design of the driver.