I have the ball point and the pencil in plastic.
I tried the metal one in Germany and liked it. I'm not sure the plastic ones are as good (although considerably cheaper), I think it's the weight. Also the aluminium one felt nicer to touch.
They aren't every day writers for me, I tend to leave them in my work bag as a back up. I do like the pencil for doodles tho...
I have two Sports but both FP's which are excellent writers. Free flowing, no skipping and they lay a line thats more dry than wet.
Super little pens and mine get a lot of use, 1x fine nib and 1x tedium nib.
regards, beejay
Late in spotting this - I have a Kaweco Classic Sport Inkroller - I didn't actually buy it for me but it's on my desk
Works very well - I still prefer a fountain pen but it works every bit as well as your standard run of the mill Parker Rollerball - just with an infinity of possibilities for the ink colour.