I am a quite satisfied user of LPG and i will suggest every user to use it who is finding financial difficulties in these days to make both the ends meet. Financially it is a cheaper option so one has to consider both pros and cons instead of criticizing or making fun that People are keeping Civic, Accord, Prado and were standing in queue for CNG or LPG.
I would like to remind that same cng kit, same cng cylinder, same cng filler is utilized while converting to LPG...
Only for better mileage, install lpg pipe inside cylinder (After cleaning of cylinder from oil and residues)
For better cold start as well as safety, install water/coolant pipes for inlet/outlets to keep kit hot, high warm and prevent gas from freezing.
In my 55 Litre CNG Cylinder, maximum LPG filling is 35 Kilogram (Although filler told me it can go beyond that too but till now i have not experimented it above than 35 Kg)