i suppose it depends on the dirt...? i have the black version with orange tartan seats and they were filthy. i used 3rd of a bucket of warm water and a good dose of biological powder. go in circular motions with a clean white damp/wet dishcloth and you will see the dirt coming off on the cloth. repeat as necessary and let dry.
for the rip, a quick repair would be to glue a patch under the rip. alternatively the covers do remove easily, remove and sew a patch underneath.
love your car. had i the space, i would have bid against you on it. glad you want to keep it stock, there aren't many limited editions left. from what i can work out less than 5
good luck