The maxus universal is a great gun and patterns great, but it is tapped for a proprietary scope rail that is made for a scope only. The use of a red dot like a fastfire necessitates altering the scope base. The rib is an odd design that prevents mounting most aftermarket sights. The gun is ill designed as a turkey gun unless you use bead only, which is perfectly fine btw.
The Remington v3 is tapped for a picatinny rail. The sx3 is a fine choice as well as is the Versamax and are tapped also. The sbe2 is a great choice and is tapped as well.
Both the maxus and sbe2 feel great to me. I bought my maxus for turkey but red dot mounting options led me back to my sbe2 and that is my primary turkey gun now.
If I was buying an all around gun for turkey and predators and ducks I would probably get a v3 or sx3 if price was an issue, if not then I would get an sbe2