Gear Vendor/Gear splitter

I had one installed on a 1998 coach with a 460 and a 3-speed transmission. I really liked having 6 speeds and especially being able to run in 2nd/over up hills; plus I could cruise at a faster speed and lower rpm's on flat ground. I sold the coach a couple of years later so I don't know how well they hold up over time. To me, it was worth the money. I think it was about $3000 installed, but that was about 15 years ago.