carbomb,

its sad that you have experienced leaking and smelly lpg conversions, but i tell you, it all depends on the conversion kit brand and installer. personally, i have a fleet of the latest 4th generation, Sequential Gas Injection (SGI) LPG KIT equipped cars, and they perform flawlessly, you wouldnt even know its lpg powered, it doesnt even smell lpg at the exhaust since its very efficient, it burns completely, no lpg smell.

but its true that backyard conversions exists, but there are also top notch lpg conversions available.

older versions 1st,2nd, and 3rd generation kits also doesnt smell or leak lpg when installed and maintained properly.