Scott at Hillside listed two main reasons; bring the tq curve even further left, and raise the compression with an earlier intake close. They have not done any builds (to my knowledge, Scott chime in) but their simulations say and Bob Woods would say that these cams really want 10.4-10.5 compression. So, until I go to bigger bore and headwork, I'm OK spending a little extra money ($50 for crank sprocket 4* advance from Andrews).
Also, an earlier poster asked about the 107 "package". Actually, Hillside bores out the stock jugs to 107, and fits them with their proprietary Wiseco pistons. As a reminder, I don't ride a bagger, I have a XBNZ, and don't ride 2-up or as heavy as most on this forum, so my style and goals are different.
TedMan