One powerful sub or two lesser subs?

I am looking at either getting one alpine type R 12" sub ported but my question is, will two type "s" running at 250w rms each ported sound better than the one alpine sub with 500w rms amp. Does the dual subs at 250w each rms or one sub at 500 get better spl and sound quality? I know alpine type R is Brtter quality than type S subs.

I will be getting an M500 alpine mono block amp. which is 500w rms at 2 ohms. Really is the 2x 12" type S alpine subs splitting 500w rms, better sound or 1 type R 12"sub running at full 500w rms better to really clarify.

Normally, 2 subs with the same power will be louder

two subs will be better for sound and system