I have used the G2 paint on several cars over the years and highly recommend it. My BMW 335i had 5 years of Michigan winters and still looked great! I will warn you that the two part coating dries fairly quick (30-35 minutes) so have all four rotors fully cleaned and taped off ready to coat prior to performing the task. The small acid brush will work fine, do the front rotors first before coating thickens. You can get the G2 paint in a custom color for example Estoril Blue:
https://www.g2usa.com/product/CBCP-335.html