Yeah, I've heard about the heater changes.... the older Extreme models would heat to 350C I believe, but the one I bought only heats to 250C, which seems to be perfect. At 250 I'm not burning the "herb" and when it's done I get the infamous burnt popcorn smell, so I believe it's working perfectly.
No, the heater hasn't been changed at all, just the placement of the sensor. The new version heats to the exact same temp as the original. Only the display reading is different.