Where can you save more, with induction cooker or LPG stoves?

According to this blog: http://sustainablog.org/2014/07/energy-efficient-induction-cooking/ Induction cooktops are 90% power efficient than LPG stoves which are only 50% efficient. The comparison is based from how fast the cooker type can heat up or can transfer the heat needed to the pan then eventually to the food you're cooking. And apparently, induction cookers are more eco-friendly as there's a lack of wasted heat unlike the LPG which obviously suggests more. But the thing is, ferromagnetic metal such as cast iron or stainless steel should be present or the main component of the cooking pan you're using. Meaning, since it's a new technology you have no choice but to keep your old pans and other cooking ware. And based from those induction-friendly cookware that I can see in malls, they're a bit pricey.

Well for me mas nakakasave kami sa induction at mas safety pa gamitin.. Mababa lang kuryente namin kahit palagi kami nagluluto before na hinde kami gumagamit ng induction ang binabayaran namin kuryente ay nasa 450 to 500 nung induction na gamit namin umabot lang ung bill ng 630 so konti lang ang nadagdag.

For me it's still the LPG stoves. Just following the advice of my kuya who shifted from lpg to induction cooker and he said to just stick with lpg as it is more cost efficient.