The near instant heat up is a big part of how I ended up with my Bambino with its "Thermojet"(Thermoblock coil thing) heater.
3s from wake to ready, it takes longer to grind and prep than to heat. I usually pull a blank shot through the clean portafilter into the cup I'm going to pull the shot in so the downstream parts aren't crashing the temperature, but that's still seconds.
Ascaso and Decent have more up-market offerings with thermoblock heaters that are similarly fast but offer more control. I wasn't 5-10x price compelled for my needs, and I'm certainly not over 100x price in to that thing... But it is a great feature that the commercial derived machines don't do.