Difference between rebuilt and replaced engine?
 

What's the difference? Is a replaced engine better?

In both cases, both are more then likely rebuilds (or remans as we call them) anyways - unless you order brand new rotor housings, rotors, etc, and build a 'new' one from scratch. As of this time, Mazda does not have 'crate' rotary engines.

The general consensus is that a reman from KD Rotary is a good choice (as they supposedly take it apart to inspect it), though sourcing one thru another means can certainly be fine.

Hope that helps!

I'm sorry but I'm still confused. My question is, is a brand new engine always better than a rebulit one?

brand new anything is better than rebuilt.

Sure, all other things being equal - meaning who ever assembles either engine takes the proper time and care to do so. Rebuilds reuse some parts which are still within factory tolerances.

Then again, if you had a carefully rebuilt rebuild (hehe) with close eye towards tolerances (or even blue printing) - it would be better then a sloppy job comprising of all new components.