I've ventured into this class of pens in the last two years and have integrated them into my everyday carry. In some instances I find fountain pens to be impracticable.
The first refillable pen I used was the Noodlers Konrad Clear demonstrator rollerball pen. This pen is exceptionally smooth. I have been filling it with Parker Quink black and the results are outstanding. It writes broadly, smoothly and vividly. The pen was supplied with two spare nib points. I use this pen on a daily basis and since there is no need to apply ANY pressure the nib is not showing any sign of slowing down. The Noodlers pen is a piston filler. This takes some getting used to. For optimal use the pen has to be full at all times. I am happy with this pen.
Secondly I also use the Schneider easy rollerball pen. This is a super tough pen that uses international fountain pen cartridges. They are cheap as well. The nib is quite sturdy. From a convenience point of view this is an excellent pen.
Many criticisms of the ink ball pen are that the nib may give up on you and the ball may fall out. This initially dissuaded me against refillable rollerball pens. However after two years of heavy usage this criticism is a fallacy as I have not experienced ANY wear or distortion of nib performance.
With a little imagination the Pilot V Ball grips are refillable I've been using one regularly with my favorite black fountain pen ink. You can just use a plier and some paper or cloth as a buffer to remove the nib and fill ink.
I've tried this with the uniball vison elite but failed.
In conclusion, with this species of pens I would recommend trying the Schneider first. I couldn't find them in South Africa, upon enquiring with the local distributor he sent me a whole bag of stationery items for free including the roller. Schneider is quite helpful and obliging
Edited by IvoryParker, 19 March 2017 - 07:37.