Theres a buisness opportunity.....do a decent LPG controller....one that monitors MAF and O2 and self learns.....looks like the current setup will require 10K tune ups....
Costs of course!!!
Car ECU driven systems SHOULD theoretically work a lot better than lamda driven systems, they piggyback off the cars ECU which is generally more sophisticated. But they need setting up and to my mind the matrix is not flexible enough, it should have more like double the amount of elements.
If the LPG ECU started too many adjustments there would be the risk of the car ECU and the LPG ECU BOTH adjusting at the same time.
On a carb car a closed loop mixer system should be quite easy to work with.
All the injection systems appear to have some issues, OMVL suffer with fragile injectors. Romano injectors can get overpressured very easily, but are reliable.
There is also liquid injection but this needs all pipes to be kept cool.
I personally think that for road use LPG has a medium future - say 20 or so years, until bio fuels come on stream.
The best way to control a system would be an ECU which did the lot and held two different maps for the two different fuels.