Ever been to a restaurant where the menu choices were so extensive that you become confused?

It's happened to me, mainly at Thai establishments. Too many delicious choices.

Right now the same applies to cars. Never in the history of the automobile have motorists have so many options, not just in makes, but models, body type, transmissions, engines and a plethora of add ons. Within the engine options we now have hybrid, petrol, diesel, and LPG, dual fuel, and electric plug-in is not far away.

The motoring world is changing rapidly. It has to. GM Holden has for some time offered alternatives to ulp. With a Commodore diesel still an unknown, Holden have broadened their outlook with other vehicles, such as diesel Captiva and also including an oil burner option in the new Cruze small car. Commodore is pushing on with an LPG option. We had the pleasure of a road test in Berlina sedan last week fitted with LPG, in addition to the standard ulp tank.

The gas tank is fitted in the boot and obviously displaced some luggage area. The trade off is the LPG Commodore increases its traveling distance by a considerable amount. Try somewhere north of about 1100 kilometres. Late in 2008 Holden reduced the cost of its dual fuel system by $1500 on Omega, Berlina and Omega ute. This meant private buyers, who were eligible for the $2000 government rebate, would pay only $1400 more than its petrol equivalent in LPG ute and only $400 more for the LPG sedan.

It's here where the sums start to make some sense. Last week in Brisbane the cost of ulp was around $1.06 a litre. At the same time LPG was 48 cents a litre. But, there is a catch. LPG may cost about half as much as petrol, but because it does not have the same energy, you need more to travel the same distance. About 20 per cent more LPG.

Even allowing for that if you travel around 15,000 to 20,000 kilometres a year, you don't have to be Einstein to work out you LPG system will be paid off in a few months, not years. Allowing for the extra LPG needed to cover the same distance the savings are in the order of 48 cents a litre each time you fill up, on the figures cited above. Both the LPG and ulp tanks are 73 litres capacity. Both are filled from pipes located in behind the fuel flap.

In the cabin there's a small switch that shows you whether you are using petrol or LPG, and you can switch between the two. A series of lights in the switch indicates how much fuel is available in each tank. Basically, the system works on its own with no driver input, other than filling the car up as per normal with either petrol, LPG or both.

If LPG runs out the car simply reverts to petrol. When starting the car gets going on petrol and automatically changes over to LPG, if that's your preferred choice.So, the experience is seamless. After a week in the Berlina we also found no difference in performance. It goes pretty hard in either guise, but, of course, driving the car hard defeats the purpose of saving fuel. The upgraded Holden Alloytec V6 engine in Omega and Berlina variants not only offers fuel savings but also achieves a significant reduction in noxious emissions.

These now meet Euro V1 certification, which do not come into effect until 2014. Perhaps the best part is that aside from losing some boot space, the whole experience is one of driving a `normal' Commodore. For those who travel long distances, the LPG dual fuel variant gives options, not the least the ability to run on petrol, if LPG is not available, and fill up on LPG while keeping an eye out for the cheapest petrol. The 3.6 litre Alloytec engine delivers 175 kW of power at 6500 rpm and peak torque of 325 Nm at 2400 rpm. It is mated to a four-speed auto transmission.

Commodore sedan pricing

                    3.6 litre Omega auto $39,290

                    3.6 litre Omega LPG $41,690

3.6 litre SV6 $42,790

6.0 litre SS $47,790

6.0 litre SS V series $55,290

3.6 litre Berlina V6 auto $42,790

3.6 litre Berlina V7 LPG auto $45,190

6.0 litre Berlina V8 auto $47,790