Diesel Chips - Pros and Cons?

[glend]

Here is a holiday brain teaser for you. I have been researching the diesel chip products available for the VM 2.8L CRD as used in several Jeep models over the years (but this is also aimed at any diesel owner as the issues are much the same whether your talking about the original V engines in the XJ right up through the latest CRDs in the Grands and Commanders). There seem to be a significant number of Chips available all claiming wonderous outcomes for their products: DP, Steinbauer, TDC, Diablo, DPpower, etc etc. They all seem to do very similiar things: vary injector opening durations, and vary rail pressure - at different rpm points to maximise power lower down (in the assumed strategy of more power lower down means less fueling required higher up - hence the economy improvement claims).

These chip products vary widely in price: from as little as $275 USD for the Diablo Extreme Powerpuck, TDC at $400, to the DP at $1400, and the Steinbauer is even more expensive. As a computer programmer in my younger years I know that the manufacturers are mainly charging for their development costs and "intellectual property" relating to the code, and that there is likely less than $100 in chips, circuit board, components, connectors, and wiring in these things. It concerns me greatly that there can be such a wide variance in the product pricing, and I suspect that some have more than recovered their development cost and are now just profitering in the market - or subsidising their development costs for new models coming to market (take a bow DP and Steinbauer).

Recent development in ECU reflashing seem to be able to negate the need for a 'downstream' chip to manage fueling and appears to be low cost, or at least equivalent to the lower priced chips. The GDE flash is available in several different 'Tunes' to accomodate the wishes of the users. Unfortunately, the GDE Flash requires you to remove your ECU from the vehicle and send it to the US for flashing. However, if the logistics can be overcome, this seems to be the wave of the future in relation to diesel program management. Are there Australian equivalents to the GDE Tune??

So the big questions are:

What have present users found to be the pros and cons of these various chips?

Are fuel economy claims made by the vendors justified in real life use?

Are Jeep warranties a factor in chip choice?

Would you do it again, if you could have your money back?

[turbomart]

I havent personally used any of these chips/modules but I am a diesel mechanic with some 25yrs experience.My response isnt black & white,some engines/vehicles I believe can safely be fitted with these devices whilst others not.Many modern turbo-diesels are already pushing the performance envelope with very little margin of error, so changing the programming (regardless of how) is further reducing that safety margin.Its kinda like russian roulette.
The older design motors such as the ( discontinued) nissan patrol td42 do not make a lot of power with respect to their capacity so they can be safely increased.