low end to high end
9853ss - most bottom but great everywhere including top end and mileage , used mainly for truggy or power hungry buggy drivers

2084ss - more mileage based version of 9853ss , great truggy pipe where a lil extra mileage is needed or a greatbuggy pipe when a lil extra power is needed

9901ss - "THE" buggy pipe of choice for most all novarossi users , great smoooth power delivery with good top speed and great mileage (i have been liking this pipe with 41021 for truggy only on the X7)

2096ss - the best of all the pipes , it has what are the best attributes from all the above and gets better mileage to boot , been loving it in buggy and truggy , mileage mileage mileage

9886 - unfortunately this pipe is not offered in ss , it has the most top speed of all listed but the least mileage , awesome high speed track pipe