funny you ask that......had a bird dropping on the fury the other day.....must have happened in the morning and it sat all day in direct sunlight.....got up to 80 the other day so it was baked on real good. couldnt scrape off with my fingernail. a little warm water and light rubbing then a pass with some compound and polish on a rag and couldn't tell it was there.
i used to get complaints from local builders that the clear i use was too soft.......sikkens acIII is a pretty soft clear..even though it is a collision clear, slow reducers and hardeners make the world of difference.....they couldn't understand why the clear was scratching when they wiped dust of with one of those red shop towels.....lol! i always tell them, its easier to fix a surface scratch than a chip.
its not really about hardness, but about durability. a softer clear can be more durable than a harder clear....more times than not, it is. to me it really isn't worth giving up chip resistance for more surface scratch resistance.....i always have compound and polish in stock and is quicker than feather, prime, paint, cut & buff.