Sorry , but I couldn't find the thread about painting your hardshell bags. So I'll put my 2cents in. I have a 98 r1100gs and painted my bags yesterday. No they don't look brand new, but real close to new. the color matched perfect. I bought the paint at Menards.
Krylon fusion for plastic/ color Satin.
1. lightly sand scratches with a fine sand paper
2. wipe cases down with paint thinner to get all the polish off
3. tape over the reflector and logo ( I used some leftover green masking tape)
4. this stuff drys in about 15 minutes. I gave 30 minutes between coats.
5. one can was enough for 3 coats on both cases. Leave the cases closed and paint the complete case.
I was very happy with the results.