There are many many vehicles running LPG in Australia.
My brother in law owns one of the largest importers of Kits and installers in Australia.

The kits are very successful - depending on the money you want to spend.
Older cars - those carburetor versions are the simplest to convert.
Newer cars require a fairly extensive modification - (Don't forget that newer cars also have to pass emission regulations).

Not many Mercedes have had the conversion done. Those that have them done seem to be very happy with them - there wives will tell you a different story.

The best conversions on a K/KE jet system do away with the fuel head, injectors, O2 sensor, and supply a new ECU. There is also a system to start the engine on petroleum and then change over to L.P.gas after the car is running. Further a top end lubrication system is recommended. So you can see that the cost of this optimal setup is more than the car is worth.

You need to be very careful with a K jet car and the system as mentioned in above posts. Propane and LPG is susceptible to back fire. One backfire through your inlet manifold can render your AFM and throttle plates history.