It depends... I've used all the "solutions" out there so I can rank them for you based on my experience...
In terms of ease of application:
(1 easiest......5 hardest):
1 - Dr. Color Chip (doesn't last long - must apply after polishing or will pop out)
2 - ???
3 - Langka (best on flat surfaces only - will take some patience especially if deep but holds up surprisingly well)
4 - fill/sand/buff method as health outlined above (very effective but time consuming)
5 - professional respray (best, most durable but also most expensive)
In terms of durability:
(1 very poor/barely lasts a few car washes......5 effective)
see list above
Hybrid Mode
