If you're looking for the off-road functionality of the Anti-Rock but want the heavier on-road sway bar retained, I'd look into the ORO SwayLOC. Long story short, the Tereflex version is a rip-off of ORO's SwayLOC; after hearing of Tereflex's business practices, I'll never buy a product from them:
ORO's business model isn't exactly shining either though, so it's kind of a lesser of two evils thing if you absolutely need a dual-rate bar.
That being said, I personally run an Anti-Rock and have not experienced any decrease in on-road handling. Blaine from Savvy (the original creator of the SwayLOC) was supposedly working on an improved dual-rate sway bar, but I haven't heard anything regarding that in quite some time. I'll stick with my Anti-Rock for now; if Blaine ever decides to release a new dual-rate bar I'll probably run that.