Yep I have a Lovato system with a Prins computerized lube system on a 2.0 n/a auto. Cost me $2500 US installed. Done about 40 000kms with it. So far happy.
LPG is 50% the cost of petrol here, so a big savings. I dont feel a difference in power, even though they say you lose a bit on LPG. My consumption is crap about 13.5l/100km, but my model is not considered frugal anyway. I have a 45l tank in spare wheel well which gives me a range of just over 300km which is a bit limiting but not too bad, didnt want a huge big tank in the rear so its a compromise. My spare I keep strapped to the side of the luggage compartment in an upright position. this is to protect it from theft and the elements. when going away I use a roof rack anyway so the spare either goes on the roof or stays inside depending on my requirements. all in all I'm happy and would definitely consider it on all future vehicles I own.