I ran the offroad version for a while.
Night and day difference with a chip. Not as much gains without a chip's extra timing in the low & midrange.
Build quality was below average.
Flex joint failed within a week and the pipes never lined up correctly. Though I did some "encouraging" on them to get them close enough.
I would have your stock Y-pipe modified. (2.5" flange) Probably cost the same or even less and would give the best results available while still using a Y-pipe setup.
