has anyone ever published tests on what the real savings are by moving from gu10 halogens to gu10 leds? At the moemnt it is a lot cheaper to buy replacement halogens, than to pay out extra for the eneregy saving versions.

Like, how much does it cost to have a halogen on per week compared to an LED version? Will the led versions actually last less or more? I sthe only saving on the power bill? Or does each LED gu10 last twice as long as 1 halogen etc. (on average of course!)

thanks!