Well after much thought and concern I would be wasting my money I went ahead and ordered the QQ Thunder Mtn Baffles for my SE II's on my Heritage. What a pleasant surprise. They turned out to be perfect and seem to have had no negative effect on performance. My bike now has a nice deep throaty sound sound without the high pitched rap the stock SE II's had. Just loud enough to give a nice sound without pissing off the neighbors and driving my crazy cruising down the highway. Gonna half to get a new signature pic.