Spark plug - lpg

[Azazello]

I do not intend to use a specific engine oil for gpl, I will go on with my usual 15w40 (the last one was a Total, yesterday bought a Castrol gtx in preparation for the french-trip), but I was wondering if it was recommendable to use specific spark plugs... I found this one:
http://cgi.ebay.co.uk/ws/eBayISAPI....akeTrack=true&ssPageName=VIP:watchlink:top:en

Quite expensive related to normal ones, but still affordable, if it's worth...
What do you think, are they just trying to have my money with a new useless toy or are those spark plugs really an improvement for my engine work and life?

 

[angel]

If your R4 runs fine on normal plugs, don't bother replacing them.

Marketing hype usually circles around parts that the average driver can recognize and/or replace easily. Many people will try to sell you that magic fuel, oil, air filter, spark plug...but not a connecting rod, driveshaft, brake wheel cylinder, gearbox oil...simply because an average driver isn't familiar with them. It's amazing how misleading can advertising be in our society...

 

[Azazello]

And I recognize myself as an easy target...
I was told that lpg reaches higher temp during combustion so needs a "colder" spark plug... efectively my temp gauge measures sometimes some value that are a bit too high on my own, even a bit more than 200°F... I thought it was the summer, but now this doubt...
I even thought if it could be better to swap my 86°C thermostat with a 75°C one...

Thank you Angel!