Hey guys, I like the 3000W. Please note that it works well for a 5G system. Yes, definitely insulate your kettle.
Takes about 25 minutes from tap temperature to strike temp. So ~60F to ~170F (or 15C to 76C) for about 4gallons of water.
This usually allows time to setup a couple of things, (mill the grain, weigh the hops, etc.)
Then once the wort is in the kettle (post mash) it probably take another 25 minutes to get to boil. This gives me time to empty and rinse my mash tun and do a couple of other things to prep for when the first hop addition. There isn't alot of waiting around generally.
Did some reading into how the 3000W would perform on a 10G system. It would be a bit different and would test the boundaries of the 3000W.
Given the diameter of the cooking surface is not huge, a slim and tall kettle would work best. Something like this:
http://www.northernbrewer.com/shop/brewing/brewing-equipment/brew-kettles/tall-boy-stainless-steel-brew-kettle.htmlOr this kettle:
http://www.northernbrewer.com/shop/brewing/brewing-equipment/brew-kettles/megapots/megapot-1-2-brew-kettle-with-ball-valve-brewing-thermometer.htmlWebrestaurantstore.com has a 3500W model. It's probably only a matter of time before they have some induction burners that are even more powerful AND affordable.
With regards to going electric; it will definitely be more expensive upfront. For example you can pick up a propane burner for $50 vs these induction-ready is many times more expensive. But then you don't have to worry about refilling propane and other issues discussed above.
There are other ways you can go electric which are less expensive than induction. Water heater elements, etc. Just make sure you know what you're doing (GFCI protection) or better yet, find an electrician who likes beer and ask for advice.