ask your rel dealer ,or better yet.. rel north american distributor......rel stentor 3 ,will smoke 2 stratas,or 2stadiums it will even beat studio ii(old model)...just no contest .You read alot of threads, yes 2 should be better than 1 ...it is usually for same size or similar make.BUT when you say bigger (hope better)like stentor 3,this thing is fast, deep ,DEEP,moves air big time ...you can't compare even 4 small subs..Besides stereo doesn't exsist for deep bass . YES i do have one,SEAMLESS