initial D is REAL!

Hey guys, I have read the FAQ, so please dont tell me to search. I had a s4 t2 engine that I blew. It was a Mazda remanufactured engine, soa lot of the parts on it were pretty new. I just got a used s5 engine that was supposed to be built by R and R in upland CA. I had a few minor qusetions

1)Is the s5 water pump any better than s4? Im thiking about putting my s4 wp on, im pretty sure its remanufactured

2)Is the oil pump any better for s4 vs s5?

3)Ive read the s5 intake manifold is better, but I cant tell the difference. I put them side to side and they pretty much look the same. Is there an easy way to tell?

Thanks guys