IMHO is...
In MY Humble Opinion.
The striping depends a lot on the color and detail fo the rest of the car. Mine is dark metallic blue, with black bmpers and black valances. So the black stripe lettering looks like it belongs there.
This week though, I am changing mine over to chrome bumpers, and body color SE spoiler. So the stripe has got to go. I hope it comes off clean!!!
My last 914 was dark grey, and had the cheapo ABS rocker covers in gray with the PORSCHE lettering in relief on them. I REALLY liked that look. It lowers the the lines of the car for a tougher looking stance.
For your silver car, I voted no stripes. The ABS rockers would look good on it, but I have never found another set.
Why did you part out the yellow one? It looks dang nice! Did it die of rust?