If the pan is larger than the burner then the edges could be "cool". As I remember, my Fagor guide recommended no more than an inch larger than the burner diameter (e.g., 10" pan on 9" burner). I'll have to recheck tomorrow. See also the cookware link below. If the pan is smaller than the burner ... "will the reduction in power be noticeable?" You mean that your electrical bill will be lower? That a pan-sensing feature will decrease the burner output (so that a 10 setting is effectively, say, a 7 setting)? That there will be an electromagnetic field beyond the pan edge that is wasted (note that there won't be any reduction in cooking power)? Something else? Here is a link that might be useful: cookware: diameter extension ...

There are two kinds of flat bottom woks that work on induction, the kind that is squished flat on the bottom, and the kind that is flat on the bottom and curved on the inside. You might want to try the latter if you're a traditional wok cook. Since gas is not an option, then the question isn't whether the induction will work with your old cookware, but whether induction or plain electric will suit your cooking best. If you want to wok with high heat you'll probably prefer induction, even with a new flat bottomed induction wok. If you're happy with your results on electric and aren't looking for more power and responsiveness then save your money. On some induction units the cookware only has to be within 1/4" of the surface, but as Weedmeister said, the power drops off. The best result will be with direct contact between the unit and the pan. Even though the round bottom of a traditional wok might be pretty much in contact, most inductors need a pan that's minimum of 4" diameter to register with the sensor and work. Induction spreads up the iron in the sides of the pan, which is why it works so well with a wok--this is a similar effect to the way the flames of an open fire heats the sides of the wok. Regarding your waffle iron, the surface of the cooktop only gets warm from the heat of the pan, rather than from the energy of the inductors. If it's square the corners might not heat as well as the center, but that's something worth experimenting with. If the handle is iron, it'll get hot, but you should be able to use an oven mitt or something to flip it. The mitt won't burn or anything. Or you could put a wood or silicone sheath over the handle. They sell the silicone ones. Fori -- does this mean you're enjoying your new cooktop?

With conventional flat circular coil hobs, the heated zone is over the coil windings, and should be symmetrical about the coil center (it more or less has to be). The coil center should be aligned with the surface markings, but might not be and this can be checked by watching boiling water patterns. Correction requires cooktop disassembly and coil adjustment. Heating will be indirect above the very center of the coil due to fewer field lines there. The toroidal field above the coil will cause a ring shaped heating of the pan base extending from a bit away from the center to the edge of the coil, which may extend to the pan base edge, but might be smaller than the pan. If larger, then edge heating might reveal some added heating there as the farther radial field lines have to intersect the inductive material at the edge of the pan. Detection of the heating pattern somewhat depends on the pan base construction. Thin 400 series stainless steel without copper or aluminum layers will most easily reveal the field pattern; heavy layers will spread the heat and make the field structure difficult to deduce.

In 2005 when I renovated our kitchen I bought Calphalon tri-ply cookware with glass lids. We just replaced our now broken old cooktop with an induction range. I purchased identical Calphalon tri-ply pots and pans on Amazon, except these of course are induction compatible. I decided that I only need four pans at this point: 5 quart dutch oven, eight quart pot, 3.5 quart pan, and a 10" frying pan. I can get by without purchasing little sauce pans. These pans are 10" (give or take) in diameter so the lids are interchangeable. There is more space in my cabinets, which I am grateful for!