What is the difference between B.U.D.S. and B.U.D.S.2 ?

The main difference is in compatibility with newer models.

B.U.D.S. supports  models produced between:

Jet Ski- 2006-2015,

Snowmobiles, SSV and Roadsters-2006-2016,

ATVs-2006-2017.

B.U.D.S. 2 supports newer models:

Jet Ski- 2016 and newer,

Snowmobiles, SSV and Roadsters- 2017 and newer,

ATVs-2018 and newer.

Keep in mind that B.U.D.S. 2 does NOT support older versions!