Welcome dchu,
If your paint is only 6 months old with slights swirls, you may not even need SSR 2.5
I would start with SSR1 with a polishing pad and check your progress. It may require more than 1 pass to achieve the results that you want.
Remember to always use the least aggressive comination first
BTW, what type of car and what color is it?
Congrats on the new ride and enjoy your stay here at DC
"J"