There are some tests in the
RDM thread which seem to hint at Maxentius being quite awesome for RDM.
There are some other similar tests in the GEO and SCH threads, granted the gap is not as large for the latter given the better/larger options available, in general.
Go and read the post I link and please follow the further discussion in the following posts to get yourself a better idea. But in general yes, Maxentius is pretty nice. Better than an average Grioavolr, worse than stuff like Perf Grio/Raetic+1.
MaxentiusMH/KajaRodOH seems to be the absolute BiS in terms of pure damage output. Of course that requires you going with a sub that gives you dualwield.