Not familiar with Victron, or have personal experience with those that own it. But, they do have a good following and reputation.
The Trimetric brand I've friends that are very pleased with their results. And I've ready many heavy into Boon Docking that won't leave home without a Trimetric.
I know more from firsthand friends, and from reading positive input about Trimetric, so that is the way I'd lean if shopping.
That being said, I a do have almost a full Magnum coach. MS2812 with AGS/SBC/ARC-50/BMK - the only unit I have not Magnum, is the MidNite Classic150 Solar Controller. Magnum did come out with the PT-100 Controller a few months after my install, so if doing this today, I'd do a real close comparison between the PT-100 and the Classic150. In the above mix, the BMK is the measurement, of course thru a Shunt, that also requires a display module too.
Happy hunting,
Smitty