Product review (3 stars): Induction is the best and fastest way to cook with cast iron cookware, but this one isn't recommended
Although this is a quick, safe (no flame) way to cook, this cooker is not the one you want.  First of all, for any induction cooker, you need to have magnetic cookware, which you can check with any refrigerator magnet, one of which is included with the Rosewill induction cooker.  It turns out that not all stainless steel is magnetic, although cast iron cookware is.

Induction cooking is the fastest way to cook using cast iron cookware, as it heats up immediately, and responds immediately to raising or lowering the temperature.  It is as - or more - responsive than a gas flame.  Using magnetic stainless steel, I was surprised at how fast it would boil water!

The problems with the Rosewill Induction Cooker are twofold:
1) the temperature is only adjustable by 50 degrees at a time.  The range is 150 to 450 degrees, with the default at 425 degrees (imho, way too hot.  It would be much better if you could adjust it by 5, 10 or 25 degrees.  Or you can adjust the wattage, which ranges from 300Wto 1800W, with the default of 1200W.
2) On the second use, I started getting many E0 errors indicating an internal fault, call the help line.  They usually resolved themselves in less than a minute, but they are unsettling, and indicate a poor product design or poor quality control, and they shake my confidence in this purchase.

I wouldn't recommend this item to anyone.  Look for a better one, although I don't know what to recommend to you.