I have used the SSRs in the daytime with great results but as mentioned above the heat will kill you sometimes. If you are working in direct sunlight you will find that they break down faster & dust a little more. With a bit of experimentation you can find the right amount of product & learn...
I topped it with UPP and had no issues...it was slick as all get out. Being obsessive I had to top that with Pinnacle Paste Glaz which was awesome. Folks said they'd never seen a Diamond Graphite G look so good.