I've owned many electric kettles in my day. Most were utter crap. But two have really stood up to repeated use and have great features.1
The best is the Cuisinart CPK-17. It's a big boy, holding 1.7L but it also heats a full pot in just a few minutes. The two best features of this kettle are the variable temperature settings and the Keep Warm function. The variable temperature is accurate enough (less the 5 deg. variation from stated temperature) but the Keep Warm function will constantly cycle the heating element to maintain the set temperature for 30 minutes. That's pretty nice. I also like that "Boil" is an option. Too many kettles just make warm water. I can make 1.7L of boiling water faster in this kettle than I can on my gas stove.
The runner up is the Adagio UtiliTEA. It's a small kettle (30 oz.) but it heats up very quickly. Like the Cuisinart, it has a variable temperature adjustment but rather than discrete predetermined temperatures, it is a continuous adjustment. It's really trial and error and I found it to have more error than I liked. The big bonus is extremely short heating times.
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