I think certain mufflers change their tone drastically when adding a full xpipe. I know both eisenmanns and the Remus race sound totally different with an xpipe compared to just the mufflers themselves. I feel the Remus n eisenmann drone/tone was engineered to be just by themselves where mufflers like gintanis race or sport sound the same just more.
I'd just double check n make sure you like the sound the Remus race/xpipe combo sounds. I heard fabspeed xpipe and aa catless xpipe with Remus race and it sounded like ass IMO. Way too much rasp, like the car is farting really loud.
If you want the higher pitch sound then you'll need an xpipe, as any axle back only changes tone and after like 4k rpm the sound kind of dies off. If i knew this earlier I wouldve just shopped for a full exhaust. PM me if you need info on exhaust setup combos, I heard/owned a few