Rollerball brands of refills?

[MTHALL720]

I'm a long time fountain pen user but am now considering a,rollerball.  Are there brands of rollerball refills that would give good rich black color and tend to be a smooth writer in Broad size?   Thanks very much. 

[Chouffleur]

 

I'm a fan of the Uni-ball Signo Broad UM-153 Gel Pen and the UMR-10 refill. Others may have alternative views (however mistaken).

[MTHALL720]

Thank you