its definatly a good idea if using that amount of fuel the only problem with the heads on certain hondas is that they have soft valve seats and the easy way round is either fitting hardened seats or a valve lubrication system, and you will not need any form of k pro or any other managent system as the latest gas systems come with a stand alone unit that controls all the fueling aspects, and you will actually get more power if you tune it to run solely on gas not a compremise between the two, the cost for a 4 cylinder car on a syquential gas sytem will cost you around 1k and should only be done by an lpga aproved installer, i know all this because iv fitted lpg systems for over 10 years and had lots of performance cars running on lpg even a turbo crx and eg as well as 2 impreza with no problems at all its all in the equipment used and level or expiriance